Search Results

Search found 20188 results on 808 pages for 'wireless network'.

Page 240/808 | < Previous Page | 236 237 238 239 240 241 242 243 244 245 246 247  | Next Page >

  • Which network protocol to use for lightweight notification of remote apps (Delphi 2005)

    - by Chris Thornton
    I have this situation.... Client-initiated SOAP 1.1 communication between one server and let's say, tens of thousands of clients. Clients are external, coming in through our firewall, authenticated by certificate, https, etc.. They can be anywhere, and usually have their own firewalls, NAT routers, etc... They're truely external, not just remote corporate offices. They could be in a corporate/campus network, DSL/Cable, even Dialup. Currently, clients push new data to the server and pull new data from the server on 15-minute polling loop. The server currently does not push data - the client hits the "messagecount" method, to see if there is new data to pull. If 0, it sleeps for another 15 min and checks again. We're trying to get that down to 7 seconds. If this were an internal app, with one or just a few dozen clients, we'd write a cilent "listener" soap service, and would push data to it. But since they're external, sit behind their own firewalls, and sometimes private networks behind NAT routers, this is not practical. So we're left with polling on a much quicker loop. 10K clients, each checking their messagecount every 10 seconds, is going to be 1000/sec messages that will mostly just waste bandwidth, server, firewall, and authenticator resources. So I'm trying to design something better than what would amount to a self-inflicted DoS attack. I don't think it's practical to have the server send soap messages to the client (push) as this would require too much configuration at the client end. But I think there are alternatives that I don't know about. Such as: 1) Is there a way for the client to make a request for GetMessageCount() via Soap 1.1, and get the response, and then perhaps, "stay on the line" for perhaps 5-10 minutes to get additional responses in case new data arrives? i.e the server says "0", then a minute later in response to some SQL trigger (the server is C# on Sql Server, btw), knows that this client is still "on the line" and sends the updated message count of "5"? 2) Is there some other protocol that we could use to "ping" the client, using information gathered from their last GetMessageCount() request? 3) I don't even know. I guess I'm looking for some magic protocol where the client can send a GetMessageCount() request, which would include info for "oh by the way, in case the answer changes in the next hour, ping me at this address...". Also, I'm assuming that any of these "keep the line open" schemes would seriously impact the server sizing, as it would need to keep many thousands of connections open, simultaneously. That would likely impact the firewalls too, I think. Is there anything out there like that? Or am I pretty much stuck with polling? TIA, Chris

    Read the article

  • Why am I getting a "network is unreachable" error on Ubuntu Server?

    - by jason328
    I'm a completely new to Ubuntu server and am having a hard time connecting the server to the internet. I first ran ping -n 8.8.8.8 connect:Network is unreachable Then I ran ifconfig Link encap:Local Loopback inet addr:127.0.0.1 Mask 255.0.0.0 inet6 addr: ::1/28Scope:host UP LOOPBACK RUNNING MTU:16436 RX packets:192 errors:0 dropped:0 overruns:0 frame:0 TX packets:192 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:15360 (15.2KB) TX bytes:15360 (15.3KB) Here is ouput for sudo lspci -n 00:00.0 0600: 8086:2580 (rev 04) 00:02.0 0300: 8086:2582 (rev 04) 00:1d.0 0c03: 8086:2658 (rev 03) 00:1d.1 0c03: 8086:2659 (rev 03) 00:1d.0 0c03: 8086:265a (rev 03) 00:1d.0 0c03: 8086:265b (rev 03) 00:1d.0 0c03: 8086:265c (rev 03) 00:1e.0 0604: 8086:244e (rev d3) 00:1e.0 0401: 8086:266e (rev 03) 00:1f.0 0601: 8086:2640 (rev 03) 00:1f.0 0101: 8086:2651 (rev 03) 00:1f.0 0c05: 8086:266a (rev 03) 00:0b.0 0200: 8086:1654 (rev 03) lshw-c network returns WARNING: you should run this program as super-user. *-network DISABLED description:Ethernet interface product: NetXtreme BCM5705_2 Gigabit Ethernet vender: Broadcom Corporation physical id:b bus info:pci@0000:0a:0b.0 logical name: eth0 capabilities: bus_master_cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=tg3 driverversion= 3.121 firmware=5705-v3.18 latency=32 mingnt=64 multicast=yes port=twister pair lsmod code returned this Module Size Used By e100 37213 0 dm_crypt 23125 1 ppdev 17113 0 psmouse 87603 0 snd_intel8x0 38570 0 snd_ac97_codec 134826 1 snd_intel8x0 ac97_bus 12730 1 snd_ac97_codec snd_pcm 97188 2 snd_intel8x0, snd_ac97_codec serio_raw 13211 0 snd_timer 29990 1 snd_pcm snd 78855 4 snd_intel8x0, snd_ac97_codec, snd_pcm,snd_timer soundcore 15091 1 snd snd_page_alloc 18529 2 snd_intel8x0, snd_pcm ext2 73795 1 parport_pc 32866 1 mac_hid 13253 0 lp 17799 0 parport 46562 3 ppdev, parport_pc,lp usbhid 47199 0 hid 99559 1 usbhid tg3 152032 0 i915 468651 1 floppy 70365 0 drm_kms_helper 46978 1 i915 drm 242038 2 i915,drm_kms_helper i2c_algo_bit 13423 1 i915 video 19596 1 i915 Again there is more but it's giving info on the driver itself. I know it works, I've used it. I assume then that my network got disabled when I installed Ubuntu Server. How do I enable it? I checked and the internet cable is connected to the D-link router. I have also used this same computer for internet access when I had Ubuntu Desktop installed so internet does work.

    Read the article

  • Windows 7 laptop with two active network connections will not perform DNS AAAA lookup under certain conditions

    - by Jeff Loughridge
    My laptop has two network interfaces. The Ethernet interface connects directly to my provider's edge router. It obtains an IPv6 address via SLAAC. I manually set an IPv6 DNS server. The wireless interface connects to a CPE router that doesn't understand IPv6. If the wireless interface is disabled, I can reach the IPv6 Internet with no problems using the Ethernet interface. I run into problems when both interfaces are enabled and the wireless interface get its IPv4 DNS server via DHCP. Let's look at two scenarios. Wireless interface obtains IPv4 DNS server via DHCP - The CPE router (192.168.0.1) sends its address as the DNS server. In this scenario, Windows 7 will not perform AAAA lookups. The browser uses IPv4 transit to reach dual stack web sites. I can't reach IPv6-only web sites using domain names. I can reach IPv6-enabled web sites using IPv6 literals instead of the domain name. Wireless interface is manually configured with OpenDNS DNS server - Windows 7 performs AAAA lookups using IPv6 transit (via the Ethernet). Everything works fine. My dual homed set-up is definitely not standard. Still, the behavior is very strange to me. A valid IPv6 interface exists in my Ethernet interface. Why won't Windows attempt AAAA lookups in scenario #1? I've included the output of ipconfig /all and netstat -rn. C:\Program Files\Console>ipconfig /all Windows IP Configuration Host Name . . . . . . . . . . . . : jake Primary Dns Suffix . . . . . . . : Node Type . . . . . . . . . . . . : Hybrid IP Routing Enabled. . . . . . . . : No WINS Proxy Enabled. . . . . . . . : No DNS Suffix Search List. . . . . . : res.openband.net Wireless LAN adapter Wireless Network Connection 2: Media State . . . . . . . . . . . : Media disconnected Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Microsoft Virtual WiFi Miniport Adapter Physical Address. . . . . . . . . : C0-CB-38-06-54-F9 DHCP Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes Wireless LAN adapter Wireless Network Connection: Connection-specific DNS Suffix . : res.openband.net Description . . . . . . . . . . . : DW1520 Wireless-N WLAN Half-Mini Card Physical Address. . . . . . . . . : C0-CB-38-06-54-F9 DHCP Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : fe80::fc39:9293:7d01:4a75%13(Preferred) IPv4 Address. . . . . . . . . . . : 192.168.0.105(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Lease Obtained. . . . . . . . . . : Wednesday, July 11, 2012 7:35:21 AM Lease Expires . . . . . . . . . . : Thursday, July 12, 2012 9:49:46 AM Default Gateway . . . . . . . . . : 192.168.0.1 DHCP Server . . . . . . . . . . . : 192.168.0.1 DHCPv6 IAID . . . . . . . . . . . : 364956472 DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-17-80-F8-14-5C-26-0A-03-23-5C DNS Servers . . . . . . . . . . . : 208.67.222.222 NetBIOS over Tcpip. . . . . . . . : Enabled Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : res.openband.net Description . . . . . . . . . . . : Intel(R) 82577LM Gigabit Network Connection Physical Address. . . . . . . . . : 5C-26-0A-03-23-5C DHCP Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes IPv6 Address. . . . . . . . . . . : 2607:2600:1:850:c0e9:211a:fd05:4e0b(Preferred) Temporary IPv6 Address. . . . . . : 2607:2600:1:850:3d29:1839:62db:c4c1(Preferred) Link-local IPv6 Address . . . . . : fe80::c0e9:211a:fd05:4e0b%12(Preferred) IPv4 Address. . . . . . . . . . . : 10.52.2.51(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.254.0 Lease Obtained. . . . . . . . . . : Monday, July 09, 2012 8:55:07 AM Lease Expires . . . . . . . . . . : Thursday, July 12, 2012 7:30:05 AM Default Gateway . . . . . . . . . : fe80::214:6aff:fe51:7f3f%12 10.52.2.1 DHCP Server . . . . . . . . . . . : 216.40.77.244 DNS Servers . . . . . . . . . . . : 2620:0:ccc::2 2620:0:ccd::2 216.40.77.126 216.40.77.244 NetBIOS over Tcpip. . . . . . . . : Enabled Ethernet adapter VMware Network Adapter VMnet1: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : VMware Virtual Ethernet Adapter for VMnet1 Physical Address. . . . . . . . . : 00-50-56-C0-00-01 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : fe80::4c61:495b:229e:281e%14(Preferred) IPv4 Address. . . . . . . . . . . : 192.168.40.1(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : DHCPv6 IAID . . . . . . . . . . . : 469782614 DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-17-80-F8-14-5C-26-0A-03-23-5C DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1 fec0:0:0:ffff::2%1 fec0:0:0:ffff::3%1 NetBIOS over Tcpip. . . . . . . . : Enabled Ethernet adapter VMware Network Adapter VMnet8: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : VMware Virtual Ethernet Adapter for VMnet8 Physical Address. . . . . . . . . : 00-50-56-C0-00-08 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : fe80::f996:61eb:8c00:45e6%15(Preferred) IPv4 Address. . . . . . . . . . . : 192.168.17.1(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : DHCPv6 IAID . . . . . . . . . . . : 486559830 DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-17-80-F8-14-5C-26-0A-03-23-5C DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1 fec0:0:0:ffff::2%1 fec0:0:0:ffff::3%1 NetBIOS over Tcpip. . . . . . . . : Enabled C:\Program Files\Console>netstat -rn =========================================================================== Interface List 17...c0 cb 38 06 54 f9 ......Microsoft Virtual WiFi Miniport Adapter 13...c0 cb 38 06 54 f9 ......DW1520 Wireless-N WLAN Half-Mini Card 12...5c 26 0a 03 23 5c ......Intel(R) 82577LM Gigabit Network Connection 11...5c ac 4c f8 b8 55 ......Bluetooth Device (Personal Area Network) 14...00 50 56 c0 00 01 ......VMware Virtual Ethernet Adapter for VMnet1 15...00 50 56 c0 00 08 ......VMware Virtual Ethernet Adapter for VMnet8 1...........................Software Loopback Interface 1 =========================================================================== IPv4 Route Table =========================================================================== Active Routes: Network Destination Netmask Gateway Interface Metric 0.0.0.0 0.0.0.0 10.52.2.1 10.52.2.51 10 0.0.0.0 0.0.0.0 192.168.0.1 192.168.0.105 100 10.52.2.0 255.255.254.0 On-link 10.52.2.51 261 10.52.2.51 255.255.255.255 On-link 10.52.2.51 261 10.52.3.255 255.255.255.255 On-link 10.52.2.51 261 127.0.0.0 255.0.0.0 On-link 127.0.0.1 306 127.0.0.1 255.255.255.255 On-link 127.0.0.1 306 127.255.255.255 255.255.255.255 On-link 127.0.0.1 306 192.168.0.0 255.255.255.0 On-link 192.168.0.105 306 192.168.0.105 255.255.255.255 On-link 192.168.0.105 306 192.168.0.255 255.255.255.255 On-link 192.168.0.105 306 192.168.17.0 255.255.255.0 On-link 192.168.17.1 276 192.168.17.1 255.255.255.255 On-link 192.168.17.1 276 192.168.17.255 255.255.255.255 On-link 192.168.17.1 276 192.168.40.0 255.255.255.0 On-link 192.168.40.1 276 192.168.40.1 255.255.255.255 On-link 192.168.40.1 276 192.168.40.255 255.255.255.255 On-link 192.168.40.1 276 224.0.0.0 240.0.0.0 On-link 127.0.0.1 306 224.0.0.0 240.0.0.0 On-link 10.52.2.51 261 224.0.0.0 240.0.0.0 On-link 192.168.0.105 306 224.0.0.0 240.0.0.0 On-link 192.168.40.1 276 224.0.0.0 240.0.0.0 On-link 192.168.17.1 276 255.255.255.255 255.255.255.255 On-link 127.0.0.1 306 255.255.255.255 255.255.255.255 On-link 10.52.2.51 261 255.255.255.255 255.255.255.255 On-link 192.168.0.105 306 255.255.255.255 255.255.255.255 On-link 192.168.40.1 276 255.255.255.255 255.255.255.255 On-link 192.168.17.1 276 =========================================================================== Persistent Routes: None IPv6 Route Table =========================================================================== Active Routes: If Metric Network Destination Gateway 12 261 ::/0 fe80::214:6aff:fe51:7f3f 1 306 ::1/128 On-link 12 13 2607:2600:1:850::/64 On-link 12 261 2607:2600:1:850:3d29:1839:62db:c4c1/128 On-link 12 261 2607:2600:1:850:c0e9:211a:fd05:4e0b/128 On-link 12 261 fe80::/64 On-link 13 281 fe80::/64 On-link 14 276 fe80::/64 On-link 15 276 fe80::/64 On-link 14 276 fe80::4c61:495b:229e:281e/128 On-link 12 261 fe80::c0e9:211a:fd05:4e0b/128 On-link 15 276 fe80::f996:61eb:8c00:45e6/128 On-link 13 281 fe80::fc39:9293:7d01:4a75/128 On-link 1 306 ff00::/8 On-link 12 261 ff00::/8 On-link 13 281 ff00::/8 On-link 14 276 ff00::/8 On-link 15 276 ff00::/8 On-link =========================================================================== Persistent Routes: None

    Read the article

  • sendto: Network unreachable

    - by devin
    Hello. I have two machines I'm testing my code on, one works fine, the other I'm having some problems and I don't know why it is. I'm using an object (C++) for the networking part of my project. On the server side, I do this: (error checking removed for clarity) res = getaddrinfo(NULL, port, &hints, &server)) < 0 for(p=server; p!=NULL; p=p->ai_next){ fd = socket(p->ai_family, p->ai_socktype, p->ai_protocol); if(fd<0){ continue; } if(bind(fd, p->ai_addr, p->ai_addrlen)<0){ close(fd); continue; } break; } This all works. I then make an object with this constructor net::net(int fd, struct sockaddr *other, socklen_t *other_len){ int counter; this->fd = fd; if(other != NULL){ this->other.sa_family = other->sa_family; for(counter=0;counter<13;counter++) this->other.sa_data[counter]=other->sa_data[counter]; } else cerr << "Networking error" << endl; this->other_len = *other_len; } void net::gsend(string s){ if(sendto(this->fd, s.c_str(), s.size()+1, 0, &(this->other), this->other_len)<0){ cerr << "Error Sending, " << s << endl; cerr << strerror(errno) << endl; } return; } string net::grecv(){ stringstream ss; string s; char buf[BUFSIZE]; buf[BUFSIZE-1] = '\0'; if(recvfrom(this->fd, buf, BUFSIZE-1, 0, &(this->other), &(this->other_len))<0){ cerr << "Error Recieving\n"; cerr << strerror(errno) << endl; } // convert to c++ string and if there are multiple trailing ';' remove them ss << buf; s=ss.str(); while(s.find(";;", s.size()-2) != string::npos) s.erase(s.size()-1,1); return s; } So my problem is, is that on one machine, everything works fine. On another, everything works fine until I call my server's gsend() function. In which I get a "Error: Network Unreachable." I call gercv() first before calling gsend() too. Can anyone help me? I would really appreciate it.

    Read the article

  • Curl_errno=55, "Failed sending network data."

    - by 4dplane
    Hi all: I have a php script that updates a database via an api. This script works on one server but not on another. Both servers have curl enabled and they have php 5.2.6 or above. The error happens in the do_put() method. The rest of the script seems to be fine. I have found that: curl_errno= 55 = "Failed sending network data". curl_error= select/poll returned error <?php //phpinfo(); require_once "class.DelveAuthUtil.php"; $access_key = ""; $secret = "W"; $org_id = ""; $media_id = ""; $new_tag_name = "uvideo"; $assign_tag_to_media_url = "http://api..com/rest/organizations/$org_id/media/$media_id/properties/tags/$new_tag_name"; $signed_create_new_tag_url = DAU::authenticate_request("PUT", $assign_tag_to_media_url, $access_key, $secret); # perform the creation of the new custom property $put_response = do_put($signed_create_new_tag_url); # Execute the POST function do_post($url, $params=array()) { # Combine parameters $param_string = ""; foreach ($params as $key => $value) { $value = urlencode($value); $param_string = $param_string . "&$key=$value"; } // Get the curl session object $session = curl_init($url); // Set the POST options. curl_setopt ($session, CURLOPT_POST, true); curl_setopt ($session, CURLOPT_POSTFIELDS, $param_string); curl_setopt($session, CURLOPT_HEADER, false); curl_setopt($session, CURLOPT_RETURNTRANSFER, true); // Do the POST and then close the session $response = curl_exec($session); curl_close($session); return $response; } # Execute the PUT function do_put($url) { // Get the curl session object $session = curl_init($url); print(" <br> session= " . $session . "<br>"); // Set the PUT options. print ("opt0= " . curl_setopt($session, CURLOPT_VERBOSE, TRUE) . "<br>"); print ("opt1= " . curl_setopt ($session, CURLOPT_PUT, true) . "<br>"); print ("opt2= " . curl_setopt ($session, CURLOPT_HEADER, false) . "<br>"); print ("opt3= " . curl_setopt ($session, CURLOPT_RETURNTRANSFER, true) . "<br>"); // Do the PUT and then close the session $response = curl_exec($session); if (curl_errno($session)) { print ( "curl_errno= " . curl_errno($session). "<br>"); print( "curl_error= " . curl_error($session) . "<br>"); } else { curl_close($session); } } I have small lead in the Apache log - there is an SSL issue that I do not know how to resolve. [Thu Mar 25 15:57:58 2010] [warn] Init: You should not use name-based virtual hosts in conjunction with SSL!! [Thu Mar 25 15:57:58 2010] [notice] Apache/2.2.3 (CentOS) configured -- resuming normal operations [Thu Mar 25 15:58:59 2010] [notice] caught SIGTERM, shutting down [Thu Mar 25 15:58:59 2010] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Thu Mar 25 15:58:59 2010] [warn] RSA server certificate is a CA certificate (BasicConstraints: CA == TRUE !?) [Thu Mar 25 15:58:59 2010] [warn] RSA server certificate CommonName (CN) `yourvps.a2hosting.com' does NOT match server name!? [Thu Mar 25 15:58:59 2010] [warn] RSA server certificate is a CA certificate (BasicConstraints: CA == TRUE !?) [Thu Mar 25 15:58:59 2010] [warn] RSA server certificate CommonName (CN) `yourvps.a2hosting.com' does NOT match server name!? [Thu Mar 25 15:58:59 2010] [warn] Init: SSL server IP/port conflict: my1.com:443 (/home/httpd/my.com/conf/kloxo.my1.com:69) vs. elggtest.my1.com:443 (/home/httpd/elggtest.my1.com/conf/kloxo.elggtest.my1.com:71) [Thu Mar 25 15:58:59 2010] [warn] Init: You should not use name-based virtual hosts in conjunction with SSL!! [Thu Mar 25 15:58:59 2010] [notice] Digest: generating secret for digest authentication ... [Thu Mar 25 15:58:59 2010] [notice] Digest: done [Thu Mar 25 15:59:00 2010] [warn] RSA server certificate is a CA certificate (BasicConstraints: CA == TRUE !?) [Thu Mar 25 15:59:00 2010] [warn] RSA server certificate CommonName (CN) `yourvps.a2hosting.com' does NOT match server name!? [Thu Mar 25 15:59:00 2010] [warn] RSA server certificate is a CA certificate (BasicConstraints: CA == TRUE !?) [Thu Mar 25 15:59:00 2010] [warn] RSA server certificate CommonName (CN) `yourvps.a2hosting.com' does NOT match server name!? [Thu Mar 25 15:59:00 2010] [warn] Init: SSL server IP/port conflict: my1.com:443 (/home/httpd/my1.com/conf/kloxo.my1.com:69) vs. elggtest.my1.com:443 (/home/httpd/elggtest.my1.com/conf/kloxo.elggtest.my1.com:71) [Thu Mar 25 15:59:00 2010] [warn] Init: You should not use name-based virtual hosts in conjunction with SSL!! [Thu Mar 25 15:59:00 2010] [notice] Apache/2.2.3 (CentOS) configured -- resuming normal operations[/PHP] Any help would be great! Thanks, 4dplane

    Read the article

  • Why does my ping command (Windows) results alternate between "timeout" and "network is not reachable"?

    - by Sopalajo de Arrierez
    My Windows is in Spanish, so I will have to paste console outputs in that language (I think that translating without knowing the exact terms used in english versions could give worse results than leaving it as it appears on screen). This is the issue: when pinging a non-existent IP from a WinXP-SP3 machine (clean Windows install, just formatted), I get sometimes a "Timeout" result, and sometimes a "network is not reachable" message. This is the result of: ping 192.168.210.1 Haciendo ping a 192.168.210.1 con 32 bytes de datos: Tiempo de espera agotado para esta solicitud. Respuesta desde 80.58.67.86: Red de destino inaccesible. Respuesta desde 80.58.67.86: Red de destino inaccesible. Tiempo de espera agotado para esta solicitud. Estadísticas de ping para 192.168.210.1: Paquetes: enviados = 4, recibidos = 2, perdidos = 2 (50% perdidos), Tiempos aproximados de ida y vuelta en milisegundos: Mínimo = 0ms, Máximo = 0ms, Media = 0ms 192.168.210.1 does not exist on the network. DHCP client is enabled, and the computer gets assigned those network config by the router. My IP: 192.168.11.2 Netmask: 255.255.255.0 Gateway: 192.168.11.1 DNS: 80.58.0.33/194.224.52.36 This is the output from "route print command": =========================================================================== Rutas activas: Destino de red Máscara de red Puerta de acceso Interfaz Métrica 0.0.0.0 0.0.0.0 192.168.11.1 192.168.11.2 20 127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1 192.168.11.0 255.255.255.0 192.168.11.2 192.168.11.2 20 192.168.11.2 255.255.255.255 127.0.0.1 127.0.0.1 20 192.168.11.255 255.255.255.255 192.168.11.2 192.168.11.2 20 224.0.0.0 240.0.0.0 192.168.11.2 192.168.11.2 20 255.255.255.255 255.255.255.255 192.168.11.2 192.168.11.2 1 255.255.255.255 255.255.255.255 192.168.11.2 3 1 Puerta de enlace predeterminada: 192.168.11.1 =========================================================================== Rutas persistentes: ninguno The output of: ping 1.1.1.1 Haciendo ping a 1.1.1.1 con 32 bytes de datos: Tiempo de espera agotado para esta solicitud. Tiempo de espera agotado para esta solicitud. Tiempo de espera agotado para esta solicitud. Tiempo de espera agotado para esta solicitud. Estadísticas de ping para 1.1.1.1: Paquetes: enviados = 4, recibidos = 0, perdidos = 4 1.1.1.1 does not exist on the network. and the output of: ping 10.1.1.1 Haciendo ping a 10.1.1.1 con 32 bytes de datos: Respuesta desde 80.58.67.86: Red de destino inaccesible. Tiempo de espera agotado para esta solicitud. Tiempo de espera agotado para esta solicitud. Respuesta desde 80.58.67.86: Red de destino inaccesible. Estadísticas de ping para 10.1.1.1: Paquetes: enviados = 4, recibidos = 2, perdidos = 2 (50% perdidos), 10.1.1.1 does not exist on the network. I can do some aproximate translation of what you demand if necessary. I have another computers in the same network (WinXP-SP3 and Win7-SP1), and they have, too, this problem. Gateway (Router): Buffalo WHR-HP-GN (official Buffalo firmware, not DD-WRT). I have some Linux (Debian/Kali) machine in my network, so I tested things on it: ping 192.168.210.1 PING 192.168.210.1 (192.168.210.1) 56(84) bytes of data. From 80.58.67.86 icmp_seq=1 Packet filtered From 80.58.67.86 icmp_seq=2 Packet filtered From 80.58.67.86 icmp_seq=3 Packet filtered From 80.58.67.86 icmp_seq=4 Packet filtered to the non-existing 1.1.1.1 : ping 1.1.1.1 PING 1.1.1.1 (1.1.1.1) 56(84) bytes of data. ^C --- 1.1.1.1 ping statistics --- 153 packets transmitted, 0 received, 100% packet loss, time 153215ms (no response after waiting a few minutes). and the non-existing 10.1.1.1: ping 10.1.1.1 PING 10.1.1.1 (10.1.1.1) 56(84) bytes of data. From 80.58.67.86 icmp_seq=20 Packet filtered From 80.58.67.86 icmp_seq=22 Packet filtered From 80.58.67.86 icmp_seq=23 Packet filtered From 80.58.67.86 icmp_seq=24 Packet filtered From 80.58.67.86 icmp_seq=25 Packet filtered What is going on here? I am posing this question mainly for learning purposes, but there is another reason: when all pings are returning "timeout", it creates an %ERRORLEVEL% value of 1, but if there is someone of "Network is not reachable" type, %ERRORLEVEL% goes to 0 (no error), and this could be inappropriate for a shell script (we can not use ping to detect, for example, if the network is down due to loss of contact with the gateway).

    Read the article

  • Command line mode only -- successful login only brings me back to login screen

    - by seth
    whenever I log in the screen goes black, I see a glimpse of terminal-esque text, and then it brings me back to the log in screen (Ubuntu 12.04). I can enter and log in via the command line. The guest account works find. I think this happened because I edited some Xorg related file trying to make an external monitor work with my laptop. I copy pasted from a forum post so I dont recall the file or what i put in the file. Can't find the forum post again and my bash history wasn't recorded from that session. I tried reinstalling Xorg and ubuntu-desktop, nvidia, resetting any configs I could find... I'm really at a loss of what to do. Here's my /.xsession-errors: /usr/sbin/lightdm-session: 11: /home/seth/.profile: -s: not found Backend : gconf Integration : true Profile : unity Adding plugins Initializing core options...done Initializing composite options...done Initializing opengl options...done Initializing decor options...done Initializing vpswitch options...done Initializing snap options...done Initializing mousepoll options...done Initializing resize options...done Initializing place options...done Initializing move options...done Initializing wall options...done Initializing grid options...done I/O warning : failed to load external entity "/home/seth/.compiz/session/108fa6ea48f8a973b9133850948930576700000017740033" Initializing session options...done Initializing gnomecompat options...done ** Message: applet now removed from the notification area Initializing animation options...done Initializing fade options...done Initializing unitymtgrabhandles options...done Initializing workarounds options...done Initializing scale options...done compiz (expo) - Warn: failed to bind image to texture Initializing expo options...done Initializing ezoom options...done ** Message: using fallback from indicator to GtkStatusIcon (compiz:1846): GConf-CRITICAL **: gconf_client_add_dir: assertion `gconf_valid_key (dirname, NULL)' failed Initializing unityshell options...done Nautilus-Share-Message: Called "net usershare info" but it failed: 'net usershare' returned error 255: net usershare: cannot open usershare directory /var/lib/samba/usershares. Error No such file or directory Please ask your system administrator to enable user sharing. Setting Update "main_menu_key" Setting Update "run_key" Setting Update "launcher_hide_mode" Setting Update "edge_responsiveness" Setting Update "launcher_capture_mouse" ** Message: moving back from GtkStatusIcon to indicator compiz (decor) - Warn: failed to bind pixmap to texture ** (zeitgeist-datahub:2128): WARNING **: zeitgeist-datahub.vala:227: Unable to get name "org.gnome.zeitgeist.datahub" on the bus! failed to create drawable compiz (core) - Warn: glXCreatePixmap failed compiz (core) - Warn: Couldn't bind background pixmap 0x1e00001 to texture compiz (decor) - Warn: failed to bind pixmap to texture ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. compiz (decor) - Warn: failed to bind pixmap to texture compiz (decor) - Warn: failed to bind pixmap to texture ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. ** Message: No keyring secrets found for Sonic.net_356/802-11-wireless-security; asking user. [2348:2352:12678840568:ERROR:gpu_watchdog_thread.cc(231)] The GPU process hung. Terminating after 10000 ms. [2256:2283:14450711755:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14450726175:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14450746028:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14464521342:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14464541249:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14690775186:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14690795231:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14704543843:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14704566717:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14766138587:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14857232694:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14930901403:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14930965542:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14944566814:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:14944592215:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15170929788:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15170947382:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15184585015:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15184605475:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15366189036:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15410983381:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15411569689:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15431632431:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15431674438:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15457304356:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15656020938:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15656042383:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15674651268:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:15674671786:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:16052544301:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:16057387653:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:16157122849:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:16157123851:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:16157125473:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:16157126544:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 [2256:2283:16157129682:ERROR:ssl_client_socket_nss.cc(1542)] handshake with server mail.google.com:443 failed; NSS error code -5938, net_error -107 If anyone can help me out, I'd be forever grateful

    Read the article

  • Begin the Clone Wars Have!

    - by Antony Reynolds
    Creating a New Virtual Machine from an Existing Virtual Disk In previous posts I described how I set up an OEL6 machine under VirtualBox that can run an 11gR2 database and FMW 11.1.1.5.  That is great if you want the DB and FMW running in the same virtual image and it has served me well for some proof of concepts and also for some testing of different JVMs.  However I also wanted to run some testing of FMW with the database running on a separate physical machine.  So in this post I will show how to take a VirtualBox image and create a new image based on the disks from that original image. What are my Options? There is more than one way to skin a cat, or in this case to create two separate VMs that can run on different hardware.  Some of the options include: Create new virtual disk images for each new VM. Clone the existing disk images and point the new VM at the cloned images. Point the new VM at the existing snapshots. #1 is too much like hard work, install OEL twice, install a database again, install FMW again, run RCU again!  Life is too short! #2 is probably the safest way of doing things.  VirtualBox allows you to clone a disk image for use in a separate machine.  However this of course duplicates the disk and means that it is now occupying 3 times the space, once for the original disk and twice more for the two clones I would need. #3 is the most space efficient way of doing things.  It does mean however that I can only run the new “cloned” images if I have access to the original image because that is where the base snapshots reside.  However this is not a problem for me as long as I remember to keep all threee images together.  So this is the approach we will follow. Snapshot, What Snapshot? As we are going to create new virtual machines based on existing snapshots we need to figure out which snapshot to use.  We do this by opening the “Media Manager” from within VirtualBox and moving the mouse over the snapshot images until we find the snapshots we want – the snapshot name is identified in the “Attached to:” comment.  In my case I wanted the FMW installed snapshot because that had a database configured for FMW alongside the FMW software.  I made a note of the filename of that snapshot (actually I just noted the first 5 characters as that was all that was needed to uniquely identify the snapshot file). When we create the new machines we will point them at the snapshot filename we have just checked. Network or NotWork? Because we want the two new machines to communicate with each other when hosted in different physical machines we can’t use the default NAT networking mode without a lot of hassle.  But at the same time we need them to have fixed IP addresses relative to each other so that they can see each other whilst also being able to see the outside world. To achieve all these requirements I created two network adapters for each machine.  Adapter 1 was a standard NAT mapping.  This will allow each machine to get a dynamic IP address (10.0.2.15 by default) that can be used to access the external world through the VBox provided NAT gateway.  This is the same as the existing configuration. The second adapter I created as a bridged adapter.  This gives the virtual machine direct access to the host network card and by using fixed IP addresses each machine can see the other.  It is important to choose fixed IP addresses that are not routable across your internal network so you don’t get any clashes with other machines on your network.  Of course you could always get proper fixed IP addresses from your network people, but I have serveral people using my images and as long as I don’t have two instances of the same VM on the same network segment this is easier and avoids reconfiguring the network every time someone wants a copy of my VM.  If it is available I would suggest using the 10.0.3.* network as 10.0.2.* is the default NAT network.  You can check availability by pinging 10.0.3.1 and 10.0.3.2 from your host machine.  If it times out then you are probably safe to use that. Creating the New VMs Now that I had collected the data that I needed I went ahead and created the new VMs. When asked for a “Boot Hard Disk” I used the “Choose a virtual hard disk file…” link to find the snapshot I had previously selected and set that to be the existing hard disk.  I chose the previously existing SOA 11.1.1.5 install for both the new DB and FMW machines because that snapshot had the database with the RCU completed that I wanted for my DB machine and it had the SOA software installed which I wanted for my FMW machine. After the initial creation of the virtual machine go into the network setting section and enable a second adapter which will be bridged.  Make a note of the MAC addresses (the last four digits should be sufficient) of the two adapters so that you can later set the bridged adapter to use fixed IP and the NAT adapter to use DHCP. We are now ready to start the VMs and reconfigure Linux. Reconfiguring Linux Because I now have two new machines I need to change their network configuration.  In particular I need to change the hostname, update the hosts file and change the network settings. Changing the Hostname I renamed both hosts by running the hostname command as root: hostname vboxfmw.oracle.com I also edited the /etc/sysconfig file and set the correct hostname in there. HOSTNAME=vboxfmw.oracle.com Changing the Network Settings I needed to change the network configuration to give the bridged network a fixed IP address.  I first explicitly set the MAC addresses of the two adapters, because the order of the virtual adapters in the VirtualBox Manager is not necessarily the same as the order of the adapters in the guest OS.  So I went in to the System->Preferences->Network Connections screen and explicitly set the “Device MAC address” for the two adapters. Having correctly mapped the Linux adapters to the VirtualBox adapters I then set the Bridged adapter to use fixed IP addressing rather than DHCP.  There is no need for additional routing or default gateways because we expect the two machine to be on the same LAN segment. Updating the Hosts File Having renamed the machines and reconfigured the network I then updated the /etc/hosts file to refer to the new machine name add a new line to the hosts file to provide an additional IP address for my server (the new fixed IP address) add a new line for the fixed IP address of the other virtual machine 10.0.3.101      vboxdb.oracle.com       vboxdb  # Added by NetworkManager 10.0.2.15       vboxdb.oracle.com       vboxdb  # Added by NetworkManager 10.0.3.102      vboxfmw.oracle.com      vboxfmw # Added by NetworkManager 127.0.0.1       localhost.localdomain   localhost ::1     vboxdb.oracle.com       vboxdb  localhost6.localdomain6 localhost6 To make sure everything takes effect I restarted the server. Reconfiguring the Database on the DB Machine Because we changed the hostname the listener and the EM console no longer start so I need to modify the listener.ora to use the new hostname and I also need to rebuild the EM configuration because it also relies on the hostname. I edited the $ORACLE_HOME/network/admin/listener.ora and changed the listening address to the new hostname:       (ADDRESS = (PROTOCOL = TCP)(HOST = vboxdb.oracle.com)(PORT = 1521)) After changing the listener.ora I was able to start the listener using: lsnrctl start I also had to reconfigure the EM database control.  I first deconfigured it using the command: emca -deconfig dbcontrol db -repos drop This drops the repository and removes any existing registered dbcontrols. I then re-configured it using the following command: emca -config dbcontrol db -repos create This creates the EM repository and then configures and starts dbcontrol. Now my database machine is ready so I can close it down and take a snapshot. Disabling the Database on the FMW Machine I set up the database to start automatically by creating a service called “dbora”.  On the FMW machine I do not need the database running so I can prevent it auto-starting by running the following command: chkconfig –del dbora Note that because I am using a snapshot it is not a waste of disk space to have the DB installed but not used.  As long as I don’t run it, it won’t cost me anything. I can now close the FMW machine down and take a snapshot. Creating a New Domain The FMW machine is now ready to create a new domain.  When creating the domain I can point it at the second machine which is running the database.  I can potentially run these machines on two separate physical machines as long as I have the original virtual machine available to both of the physical machines. Gotchas in Snapshotting VirtualBox does not support the concept of linked machines in a network like some virtualization technologies so when creating a snapshot it is a good idea to shut both VMs down and then take a snapshot on both of them.  This is because we want to keep the database in sync with the middleware.  One way to make sure that this happens would be to place all the domain configuration files on the database server via an NFS share, this would mean that all we would need to snapshot would be the database machine because that would hold all the state and configuration. The Sky’s the Limit We have covered a simple case of having just two machines.  I have a more complicated configuration in which two machine run a RAC database off the same base OS image, and two more machines run a SOA cluster based on the same OS image.  Just remember what machine holds state and what are the consequences of taking a snapshot.

    Read the article

  • Friday Tips #33

    - by Chris Kawalek
    Happy Friday, everyone! Our tip this week is from an excellent white paper written by our own Greg King titled Oracle VM 3: Building a Demo Environment using Oracle VM VirtualBox. In it, Greg gives you everything you need to know to set up Oracle VM Server inside of Oracle VM VirtualBox for testing and demoing. The section we're highlighting below is on how to configure the network interfaces of your virtual machines: VirtualBox comes with a few different types of network interfaces that can be used to allow communication between the VM guests and the host operating system, including network interfaces that will allow the VM guests to communicate with local and wide area networks accessed from your laptop or personal computer. However, for the purpose of the demonstration environment we will limit the network communication to include access just between your desktop and the virtual machines being managed by VirtualBox. The install process for Oracle VM VirtualBox creates a single host-only network device on your laptop or personal computer. Using the host-only network device will allow you to open a browser on your desktop to access the Oracle VM Manager running within the VirtualBox VM guest. The device will only allow network traffic between the VM guests and your host operating system, but nothing outside the confines of your laptop or personal computer. We will need to add a second host-only network since the Oracle VM Server appliance has both eth0 and eth1 configured. You can choose to use eth1 on the Oracle VM Servers or not use them – the choice is yours. But, at least the host side network device will exist if you decide to use it. Greg goes on to describe in detail how to setup the network interfaces, so you can head on over to the paper and get even more info. See you next week! -Chris 

    Read the article

  • Can I be a wireless server WITHOUT offering internet?

    - by Kenny Hendrick
    I would like to pull into a truck stop and offer a folder of free documentaries to quell some of the ignorance LOL I run Linux ";-) Very happy to have made that switch by the way...and have an internal wireless in the laptop but my bus has an antenna on the roof which I connect via usb to create a wireless signal (this is the one I'd like to focus on since it will offer the most reach to all those truckers out there. My question is this. I'm running apache2 and have a bunch of videos tossed into the www folder and can access it locally and would like others that frown on paying to use the truckstops slow internet service and would like an alternative by simply logging onto me and getting the narrow content I offer freely without passwords and the like. Has anyone a good means of doing this? p.s. I've done this in the past but am getting old and forgetful (my crutch)

    Read the article

  • How to create a Semantic Network like wordnet based on Wikipedia?

    - by Forbidden Overseer
    I am an undergraduate student and I have to create a Semantic Network based on Wikipedia. This Semantic Network would be similar to Wordnet(except for it is based on Wikipedia and is concerned with "streams of text/topics" rather than simple words etc.) and I am thinking of using the Wikipedia XML dumps for the purpose. I guess I need to learn parsing an XML and "some other things" related to NLP and probably Machine Learning, but I am no way sure about anything involved herein after the XML parsing. Is the starting step: XML dump parsing into text a good idea/step? Any alternatives? What would be the steps involved after parsing XML into text to create a functional Semantic Network? What are the things/concepts I should learn in order to do them? I am not directly asking for book recommendations, but if you have read a book/article that teaches any thing related/helpful, please mention them. This may include a refernce to already existing implementations regarding the subject. Please correct me if I was wrong somewhere. Thanks!

    Read the article

  • How can I send a Wake on Wireless LAN (WoWLAN) / Wake on Demand request manually?

    - by pioto
    This is similar to, but not the same as, http://serverfault.com/questions/1721/is-wireless-wake-on-lan-possible. I know it is supposed to be possible. The question is, how do I do whatever the AirPort Basestation will do? All I can find so far is that supposedly I need to send something with Wireless Multimedia Extensions (WMM): Basically, I want to be able to wake up my Mac Mini remotely, probably using my Linux laptop. Does anyone know of a tool to do this? Basic Wake on LAN tools do not seem to be the right thing. I don't need the Sleep Proxy Service bit, because I already know the MAC address of the system I want to wake up.

    Read the article

  • Computer Networks UNISA - Chap 14 &ndash; Insuring Integrity &amp; Availability

    - by MarkPearl
    After reading this section you should be able to Identify the characteristics of a network that keep data safe from loss or damage Protect an enterprise-wide network from viruses Explain network and system level fault tolerance techniques Discuss issues related to network backup and recovery strategies Describe the components of a useful disaster recovery plan and the options for disaster contingencies What are integrity and availability? Integrity – the soundness of a networks programs, data, services, devices, and connections Availability – How consistently and reliably a file or system can be accessed by authorized personnel A number of phenomena can compromise both integrity and availability including… security breaches natural disasters malicious intruders power flaws human error users etc Although you cannot predict every type of vulnerability, you can take measures to guard against the most damaging events. The following are some guidelines… Allow only network administrators to create or modify NOS and application system users. Monitor the network for unauthorized access or changes Record authorized system changes in a change management system’ Install redundant components Perform regular health checks on the network Check system performance, error logs, and the system log book regularly Keep backups Implement and enforce security and disaster recovery policies These are just some of the basics… Malware Malware refers to any program or piece of code designed to intrude upon or harm a system or its resources. Types of Malware… Boot sector viruses Macro viruses File infector viruses Worms Trojan Horse Network Viruses Bots Malware characteristics Some common characteristics of Malware include… Encryption Stealth Polymorphism Time dependence Malware Protection There are various tools available to protect you from malware called anti-malware software. These monitor your system for indications that a program is performing potential malware operations. A number of techniques are used to detect malware including… Signature Scanning Integrity Checking Monitoring unexpected file changes or virus like behaviours It is important to decide where anti-malware tools will be installed and find a balance between performance and protection. There are several general purpose malware policies that can be implemented to protect your network including… Every compute in an organization should be equipped with malware detection and cleaning software that regularly runs Users should not be allowed to alter or disable the anti-malware software Users should know what to do in case the anti-malware program detects a malware virus Users should be prohibited from installing any unauthorized software on their systems System wide alerts should be issued to network users notifying them if a serious malware virus has been detected. Fault Tolerance Besides guarding against malware, another key factor in maintaining the availability and integrity of data is fault tolerance. Fault tolerance is the ability for a system to continue performing despite an unexpected hardware or software malfunction. Fault tolerance can be realized in varying degrees, the optimal level of fault tolerance for a system depends on how critical its services and files are to productivity. Generally the more fault tolerant the system, the more expensive it is. The following describe some of the areas that need to be considered for fault tolerance. Environment (Temperature and humidity) Power Topology and Connectivity Servers Storage Power Typical power flaws include Surges – a brief increase in voltage due to lightening strikes, solar flares or some idiot at City Power Noise – Fluctuation in voltage levels caused by other devices on the network or electromagnetic interference Brownout – A sag in voltage for just a moment Blackout – A complete power loss The are various alternate power sources to consider including UPS’s and Generators. UPS’s are found in two categories… Standby UPS – provides continuous power when mains goes down (brief period of switching over) Online UPS – is online all the time and the device receives power from the UPS all the time (the UPS is charged continuously) Servers There are various techniques for fault tolerance with servers. Server mirroring is an option where one device or component duplicates the activities of another. It is generally an expensive process. Clustering is a fault tolerance technique that links multiple servers together to appear as a single server. They share processing and storage responsibilities and if one unit in the cluster goes down, another unit can be brought in to replace it. Storage There are various techniques available including the following… RAID Arrays NAS (Storage (Network Attached Storage) SANs (Storage Area Networks) Data Backup A backup is a copy of data or program files created for archiving or safekeeping. Many different options for backups exist with various media including… These vary in cost and speed. Optical Media Tape Backup External Disk Drives Network Backups Backup Strategy After selecting the appropriate tool for performing your servers backup, devise a backup strategy to guide you through performing reliable backups that provide maximum data protection. Questions that should be answered include… What data must be backed up At what time of day or night will the backups occur How will you verify the accuracy of the backups Where and for how long will backup media be stored Who will take responsibility for ensuring that backups occurred How long will you save backups Where will backup and recovery documentation be stored Different backup methods provide varying levels of certainty and corresponding labour cost. There are also different ways to determine which files should be backed up including… Full backup – all data on all servers is copied to storage media Incremental backup – Only data that has changed since the last full or incremental backup is copied to a storage medium Differential backup – Only data that has changed since the last backup is coped to a storage medium Disaster Recovery Disaster recovery is the process of restoring your critical functionality and data after an enterprise wide outage has occurred. A disaster recovery plan is for extreme scenarios (i.e. fire, line fault, etc). A cold site is a place were the computers, devices, and connectivity necessary to rebuild a network exist but they are not appropriately configured. A warm site is a place where the computers, devices, and connectivity necessary to rebuild a network exists with some appropriately configured devices. A hot site is a place where the computers, devices, and connectivity necessary to rebuild a network exists and all are appropriately configured.

    Read the article

  • I have nice headphones. Need a wireless USB microphone so I don't have to switch to a headset to make a call

    - by mattalexx
    Right now, I have a pair of Sennheiser HD595 headphones. They are plugged into a DAC/headphone amp. I spend all day listening to music through them and they sound awesome. Then, for making calls, I have a wireless USB headset from Logitech. Problem is, I can't make calls when I'm wearing my Sennheisers but I wouldn't want to listen to music all day using the Logitech headset. So I spend my day switching in between. So the question is, how can I make calls while wearing the headphones of my choice? One thing I thought of is a wireless USB microphone that I can clip to the Sennheisers. So I'd wear the Sennheisers with this mic all day and ditch the Logitech headset. But it doesn't look like anyone makes a microphone like this. By the way, I would love if the solution didn't transmit the sound of my clacky keyboard or noisy wood flooring.

    Read the article

  • How can I obtain/build a wireless volume knob for Windows?

    - by Mr Grieves
    I use my computer as a media center and simply love it. It's an older box running XP and it works better than everything else I've tried turning into a media center (Windows 7, Vista, several Linux distros, etc). The only thing I hate is having to walk to my audio amp to turn the volume up or down. I can use the Windows volume slider or any keyboard with keys to control volume. What I'd really love is to have a wireless knob which I can put anywhere when listening to music (e.g. kitchen) which controls the volume. It seems so simple yet I can't find it anywhere. Having controls for pausing and moving to next song would also be terrific. Griffin's Powermate could do the trick but I'd really want it to be wireless. Do you know of something I can buy or build myself to serve this purpose?

    Read the article

  • How can I send a Wake on Wireless LAN (WoWLAN) / Wake on Demand request manually?

    - by pioto
    This is similar to, but not the same as, http://serverfault.com/questions/1721/is-wireless-wake-on-lan-possible. I know it is supposed to be possible. The question is, how do I do whatever the AirPort Basestation will do? All I can find so far is that supposedly I need to send something with Wireless Multimedia Extensions (WMM): Basically, I want to be able to wake up my Mac Mini remotely, probably using my Linux laptop. Does anyone know of a tool to do this? Basic Wake on LAN tools do not seem to be the right thing. I don't need the Sleep Proxy Service bit, because I already know the MAC address of the system I want to wake up.

    Read the article

  • Ops Center 12c - Update - Provisioning Solaris on x86 Using a Card-Based NIC

    - by scottdickson
    Last week, I posted a blog describing how to use Ops Center to provision Solaris over the network via a NIC on a card rather than the built-in NIC.  Really, that was all about how to install Solaris on a SPARC system.  This week, we'll look at how to do the same thing for an x86-based server. Really, the overall process is exactly the same, at least for Solaris 11, with only minor updates. We will focus on Solaris 11 for this blog.  Once I verify that the same approach works for Solaris 10, I will provide another update. Booting Solaris 11 on x86 Just as before, in order to configure the server for network boot across a card-based NIC, it is necessary to declare the asset to associate the additional MACs with the server.  You likely will need to access the server console via the ILOM to figure out the MAC and to get a good idea of the network instance number.  The simplest way to find both of these is to start a network boot using the desired NIC and see where it appears in the list of network interfaces and what MAC is used when it tries to boot.  Go to the ILOM for the server.  Reset the server and start the console.  When the BIOS loads, select the boot menu, usually with Ctrl-P.  This will give you a menu of devices to boot from, including all of the NICs.  Select the NIC you want to boot from.  Its position in the list is a good indication of what network number Solaris will give the device. In this case, we want to boot from the 5th interface (GB_4, net4).  Pick it and start the boot processes.  When it starts to boot, you will see the MAC address for the interface Once you have the network instance and the MAC, go through the same process of declaring the asset as in the SPARC case.  This associates the additional network interface with the server.. Creating an OS Provisioning Plan The simplest way to do the boot via an alternate interface on an x86 system is to do a manual boot.  Update the OS provisioning profile as in the SPARC case to reflect the fact that we are booting from a different interface.  Update, in this case, the network boot device to be GB_4/net4, or the device corresponding to your network instance number.  Configure the profile to support manual network boot by checking the box for manual boot in the OS Provisioning profile. Booting the System Once you have created a profile and plan to support booting from the additional NIC, we are ready to install the server. Again, from the ILOM, reset the system and start the console.  When the BIOS loads, select boot from the Boot Menu as above.  Select the network interface from the list as before and start the boot process.  When the grub bootloader loads, the default boot image is the Solaris Text Installer.  On the grub menu, select Automated Installer and Ops Center takes over from there. Lessons The key lesson from all of this is that Ops Center is a valuable tool for provisioning servers whether they are connected via built-in network interfaces or via high-speed NICs on cards.  This is great news for modern datacenters using converged network infrastructures.  The process works for both SPARC and x86 Solaris installations.  And it's easy and repeatable.

    Read the article

  • How do I fix my ethernet card losing network connection every few minutes with kernels 3.8.x?

    - by igoryonya
    I'm using Ubuntu 13.04. My laptop is Acer Aspire one 722-c58rr, and my ethernet card works for a few seconds at a time with kernels 3.8.x, however, kernels 3.5.x and below worked fine. On kernels 3.8.x, it works fine after boot for about a minute, then it looses network connection. When pinging to some address, it says: network address is unreachable, but it can ping it's own address. The address is statically configured. Everything was working fine before. I went to vacation, where I used WiFi and 3G connections, so I didn't notice that the problem occurred. Came back home, plugged in into the ethernet. It worked for a minute then stopped. Rebooting commutator fixed the problem. Tried to connect to a different commutator, same problem. Unplugging and plugging the cable fixes the problem for another minute. Disconnecting eth in Network manager and reconnecting it again, does the same thing. WiFi has no such problem. Tried to use a different cable that works fine on another computer, the same problem. Tried to boot with the lower kernel version, the same problem was happening until I got to the version 3.5 of the kernel series. Everything works fine on the kernel 3.5.x, but I don't want to miss out on the new kernel's features. Executing commands, when booted with 3.8 kernel series, give the following results: lspci| grep -i eth: 06:00.0 Ethernet controller: Qualcomm Atheros AR8152 v2.0 Fast Ethernet (rev c1) dmesg| grep eth1: [ 89.548291] atl1c 0000:06:00.0: atl1c: eth1 NIC Link is Up How do I fix it, while staying in the new kernel version?

    Read the article

  • UBUNTU's Network Connection Manger can't detect Huawei ETS2051 Modem device!

    - by Doctoa
    I have a modem device called Huawei ETS2051 and the Network Connection Manger can't detect it, but when I use Gnome-PPP it work fine but the problem is when I use Gnome-PPP; apps like Ubuntu software Center Can't reconice that's Iam connecting to the Internet so the app is just act like it's offline while other apps like web browsers and IM's work good under Gnome-PPP. any way what I want is to have a Full Ubuntu experince by making The Network Connection Manger detect my ETS2051. I have another 3G USB modem and The Network Connection Manger detect it and it's work just fine but the internet price for this one is high and I can't effort it so am count on that ETS2051 modem as you can see for it's low price and stable internet speed that satesfy my needs. More information: Gnome-PPP is a GUI for wvdial. the ETS2051 modem use a serial USB port. I have a Windows driver CD for the device. I have also find This qustion about the software Center acting like it's offline around wvdial and there's this launchpad bug. and am really insest to use Ubuntu Software Center so please no other software manger apps recomendation... I've also this Genius ColorPage HR6X Slim scanner that's Ubuntu can't detect it, so if you interset you can check and answer the qustion from here...

    Read the article

  • Why am I getting [mount error(22): Invalid argument] while trying to mount SMB network drive?

    - by Steve_
    Disclaimer: I am very new to Linux :) Anyway, onward: I have a fresh instance of Ubuntu Server (12.04.1 LTS) running on my network and I want to mount a network drive to the server so I can access the contents. The network drive is a SAMBA compatible drive running Darwin OS. If I run the following command: smbclient -L //192.168.0.2 -U myuser It prompts me for the password and then displays output similar to: Domain=[SERVER01] OS=[Darwin] Server=[@(#)PROGRAM:smbd PROJECT:smbx-105.4.0] Sharename Type Comment --------- ---- ------- Comp Staff's Public Folder Disk CompRaid03 Disk Dropbox Disk Groups Disk IPC$ IPC Public Disk Users Disk compstaff Disk However, when I try and mount the CompRaid03 share, using this command: sudo mount -t cifs //192.168.0.2/CompRaid03 /mnt/myshare -o username=myuser I get the same password prompt, but after putting the correct password in, I received this error: mount error(22): Invalid argument dmesg | tail returns: [23576.037373] CIFS VFS: cifs_mount failed w/return code = -22 I don't understand what is wrong with this command. I've managed to mount a share on my current (Windows 8) machine using basically the same command but with a different IP address and share name (obviously). I've spent a good few hours trying to solve this and got no where. Any help or pointers would be greatly appreciated. Thanks Steve EDIT As suggested I've also trued using "user=" instead of "username=": sudo mount -t cifs //192.168.0.2/CompRaid03 /mnt/svnrepo -o user=myuser This results in the same "Invalid argument" error.

    Read the article

  • Is it possible to host a website with Apache HTTP through a ZyXEL EQ-660R modem and a Netgear WGT624v3 wireless router?

    - by Vortico
    Essentially, I have a spare desktop computer I'd like to turn into a web server, but my modem and wireless router are very difficult to work with. I installed Apache HTTP and successfully hosted a test page which can be accessed anywhere on the LAN. However, I'm having trouble setting up the server to be accessed from my external IP address. I was supplied with a ZyXEL EQ-660R DSL modem by my ISP (CenturyLink) and bought a Netgear WGT624v3 wireless router in which to connect my laptop and spare desktop. ZyXEL's website is no help, and I don't think much of the problem is with the Netgear router. I've played with many settings and have tried to forward port 80 from the modem, but I've had no luck. Could someone direct me toward a solution or recommendations for more promising hardware? Or should I admit defeat and explore other hobbies? :)

    Read the article

  • How come I can't redirect TCP ports on this wireless router?

    - by George Edison
    I am configuring a router to redirect TCP port 5900 (yes, this is for VNC) to a specific IP address on the network. Here is what I have: From a local computer on the same network, I can telnet to 192.168.1.64 (port 5900) just fine. However, when trying to telnet to the machine (port 5900) using its external IP address, it doesn't work. (The connection times out.) The router is a Gigaset SE567, if that helps.

    Read the article

  • Biztalk Server 2009 - Failover Clustering and Network Load Balancing (NLB)

    - by FullOfQuestions
    Hi, We are planning a Biztalk 2009 set up in which we have 2 Biztalk Application Servers and 2 DB Servers (DB servers being in an Active/Passive Cluster). All servers are running Windows Server 2008 R2. As part of our application, we will have incoming traffic via the MSMQ, FILE and SOAP adapters. We also have a requirement for High-availability and Load-balancing. Let's say I create two different Biztalk Hosts and assign the FILE receive handler to the first one and the MSMQ receive handler to the second one. I now create two host instances for each of the two hosts (i.e. one for each of my two physical servers). After reviewing the Biztalk Documentation, this is what I know so far: For FILE (Receive), high-availablity and load-balancing will be achieved by Biztalk automatically because I set up a host instance on each of the two servers in the group. MSMQ (Receive) requires Biztalk Host Clustering to ensure high-availability (Host Clustering however requires Windows Failover Clustering to be set up as well). No loading-balancing option is clear here. SOAP (Receive) requires NLB to achieve Load-balancing and High-availability (if one server goes down, NLB will direct traffic to the other). This is where I'm completely puzzled and I desperately need your help: Is it possible to have a Windows Failover Cluster and NLB set up at the same time on the two application servers? If yes, then please tell me how. If no, then please explain to me how anyone is acheiving high-availability and load-balancing for MSMQ and SOAP when their underlying prerequisites are mutually exclusive! Your help is greatly appreciated, M

    Read the article

  • Copying a directory off a network drive using Objective-C/C

    - by Jeff
    Hi All, I'm trying to figure out a way for this to work: NSString *searchCommand = [[NSString alloc] initWithFormat:@"cp -R /Volumes/Public/DirectoryToCopy* Desktop/"]; const char* system_call = [searchCommand UTF8String]; system(system_call); The system() method does not acknowledge the specific string I am passing in. If I try something like: system("kextstat"); No problems. Any ideas why the find string command I'm passing in is not working? All I get is "GDB: Running ....." in xCode. I should mention that if I try the same exact command in terminal it works just fine.

    Read the article

  • Programmaticaly prevent Vista desktop search (WDS) from indexing pst files placed on mapped network

    - by Jao
    Hi! After several days and multiple attempts I didn't find any 100% solution for this trouble. My search and investigation scopes: Direct access to registry: HKLM\SOFTWARE\Microsoft\Windows Search\CrawlScopeManager\Windows\SystemIndex\WorkingSetRules HKCU\Software\Microsoft\Windows Search\Gather\Windows\SystemIndex\Protocols\Mapi HKLM\SOFTWARE\Microsoft\Windows Search\Gather\Windows\SystemIndex\Sites\ and other keys... Windows Search 3.X interfaces like ISearchManager using Microsoft.Search.Interop Microsoft.Office.Interop.Outlook classes: NameSpace, Store AD policies (useless, no effect :( Preferred technologies: VB.NET, C#. This solution must be deployed within a large organization (about 5000 wokstations). Any ideas? Thanks in advance.

    Read the article

< Previous Page | 236 237 238 239 240 241 242 243 244 245 246 247  | Next Page >