Search Results

Search found 1687 results on 68 pages for 'packet sniffing'.

Page 18/68 | < Previous Page | 14 15 16 17 18 19 20 21 22 23 24 25  | Next Page >

• Iptables: "-p udp --state ESTABLISHED"

  - by chris_l

  Hi, let's look at these two iptables rules which are often used to allow outgoing DNS: iptables -A OUTPUT -p udp --sport 1024:65535 --dport 53 -m state --state NEW,ESTABLISHED -j ACCEPT iptables -A INPUT -p udp --sport 53 --dport 1024:65535 -m state --state ESTABLISHED -j ACCEPT My question is: How exactly should I understand the ESTABLISHED state in UDP? UDP is stateless. Here is my intuition - I'd like to know, if or where this is incorrect: The man page tells me this: state This module, when combined with connection tracking, allows access to the connection tracking state for this packet. --state ... So, iptables basically remembers the port number that was used for the outgoing packet (what else could it remember for a UDP packet?), and then allows the first incoming packet that is sent back within a short timeframe? An attacker would have to guess the port number (would that really be too hard?) About avoiding conflicts: The kernel keeps track of which ports are blocked (either by other services, or by previous outgoing UDP packets), so that these ports will not be used for new outgoing DNS packets within the timeframe? (What would happen, if I accidentally tried to start a service on that port within the timeframe - would that attempt be denied/blocked?) Please find all errors in the above text :-) Thanks, Chris

  Read the article

• SSH into remote server using Public-private keys

  - by maria

  Hi, I have recently setup ssh on two linux machines (lets call them server-a, client-b). I have generated two ssh auth files on client-b machine using ssh key gen and can see both public and private files in .ssh dir. I have named them 'example' and 'example.pub'. Then I have added example.pub to sever-a's auth file. When I try to ssh into server-a it still requests a password authentication where as I want a password less login (private key on client-b is setup without password). When I try to ssh with '-v' .. get the following output: debug1: Next authentication method: publickey debug1: Trying private key: /Users/abc/.ssh/identity debug1: Offering public key: /Users/abc/.ssh/id_rsa debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,keyboard-interactive debug1: Offering public key: /Users/abc/.ssh/id_dsa debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,keyboard-interactive debug2: we did not send a packet, disable method debug1: Next authentication method: keyboard-interactive debug2: userauth_kbdint debug2: we sent a keyboard-interactive packet, wait for reply debug2: input_userauth_info_req debug2: input_userauth_info_req: num_prompts 1 Password: Please help.

  Read the article

• SSH multi-hop connections with netcat mode proxy

  - by aef

  Since OpenSSH 5.4 there is a new feature called natcat mode, which allows you to bind STDIN and STDOUT of local SSH client to a TCP port accessible through the remote SSH server. This mode is enabled by simply calling ssh -W [HOST]:[PORT] Theoretically this should be ideal for use in the ProxyCommand setting in per-host SSH configurations, which was previously often used with the nc (netcat) command. ProxyCommand allows you to configure a machine as proxy between you local machine and the target SSH server, for example if the target SSH server is hidden behind a firewall. The problem now is, that instead of working, it throws a cryptic error message in my face: Bad packet length 1397966893. Disconnecting: Packet corrupt Here is an excerpt from my ~/.ssh/config: Host * Protocol 2 ControlMaster auto ControlPath ~/.ssh/cm_socket/%r@%h:%p ControlPersist 4h Host proxy-host proxy-host.my-domain.tld HostName proxy-host.my-domain.tld ForwardAgent yes Host target-server target-server.my-domain.tld HostName target-server.my-domain.tld ProxyCommand ssh -W %h:%p proxy-host ForwardAgent yes As you can see here, I'm using the ControlMaster feature so I don't have to open more than one SSH connection per-host. The client machine I tested this with is an Ubuntu 11.10 (x86_64) and both proxy-host and target-server are Debian Wheezy Beta 3 (x86_64) machines. The error happens when I call ssh target-server. When I call it with the -v flag, here is what I get additionally: OpenSSH_5.8p1 Debian-7ubuntu1, OpenSSL 1.0.0e 6 Sep 2011 debug1: Reading configuration data /home/aef/.ssh/config debug1: Applying options for * debug1: Applying options for target-server.my-domain.tld debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: auto-mux: Trying existing master debug1: Control socket "/home/aef/.ssh/cm_socket/[email protected]:22" does not exist debug1: Executing proxy command: exec ssh -W target-server.my-domain.tld:22 proxy-host.my-domain.tld debug1: identity file /home/aef/.ssh/id_rsa type -1 debug1: identity file /home/aef/.ssh/id_rsa-cert type -1 debug1: identity file /home/aef/.ssh/id_dsa type -1 debug1: identity file /home/aef/.ssh/id_dsa-cert type -1 debug1: identity file /home/aef/.ssh/id_ecdsa type -1 debug1: identity file /home/aef/.ssh/id_ecdsa-cert type -1 debug1: permanently_drop_suid: 1000 debug1: Remote protocol version 2.0, remote software version OpenSSH_6.0p1 Debian-3 debug1: match: OpenSSH_6.0p1 Debian-3 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.8p1 Debian-7ubuntu1 debug1: SSH2_MSG_KEXINIT sent Bad packet length 1397966893. Disconnecting: Packet corrupt

  Read the article

• Cisco IOS BVI ACL: Only allow established UDP

  - by George Bailey

  Related: Cisco IOS ACL: Don't permit incoming connections just because they are from port 80 I know we can use the established keyword for TCP.. but what can we do for UDP (short of replacing a Bridge or BVI with a NAT)? Answer I found out what "UDP has no connection" means. DNS uses UDP for example.. named (DNS server) is lisenting on port 53 nslookup (DNS client) starts listening on some random port and sends a packet to port 53 of the server and notes the source port in that packet. nslookup will retry 3 times if necessary. Also the packets are so small that it does not have to worry about them coming in the wrong order. If nslookup receives a response on that port that comes from the servers IP and port then it stops listening. If the server tried to send two responses (for example a response and a response to the retry) then the server would not care if either of them made it because the client has the job to retry. In fact.. unless ICMP 3/3 packet gets through the server would not know about a failure. This is different from TCP where you get connection closed or timed out errors. DNS allows for an easy retry from the client as well as small packets.. so UDP is an excellent choice because it is more efficient. In UDP you would see nslookup sends request named sends answer In TCP you would see nslookup's machine sends SYN named's machine sends SYN-ACK nslookup's machine sends ACK and the request named's machine sends the response That is much more than is necessary for a tiny DNS packet

  Read the article

• Isolating a computer in the network

  - by Karma Soone

  I've got a small network and want to isolate one of the computers from the whole network. My Network: <----> Trusted PC 1 ADSL Router --> Netgear dg834g <----> Trusted PC 2 <----> Untrusted PC I want to isolate this untrusted PC in the network. That means the network should be secure against : * ARP Poisoning * Sniffing * Untrusted PC should not see / reach any other computers within the network but can go out the internet. Static DHCP and switch usage solves the problem of sniffing/ARP poisoning. I can enable IPSec between computers but the real problem is sniffing the traffic between the router and one of the trusted computers. Against getting a new IP address (second IP address from the same computer) I need a firewall with port security (I think) or I don't think my ADSL router supports that. To summarise I'm looking for a hardware firewall/router which can isolate one port from the rest of the network. Could you recommend such a hardware or can I easily accomplish that with my current network?

  Read the article

• server dosnt produce syn-ack

  - by steve

  I have a small program that take packets from the nfqueue . change the ip.dst to my server dst (and ttl), recalc checksum and return the packet to the nfqueue. The server and the client are linux and apache web server is run on the server and listen on port 80. i open telnet in the client to fake ip on port 80 . the packet is changed by my program and sent to the server, but the target server (the new dst ip) get the syn , but dosnt generate syn-ack (the server also belong to me , so i can see that it get the syn with checksum correct , but dosnt generate syn-ack). if i do the same , but with the real server ip as the dest, the tcp handshake is done correct (in this case i just change the ttl and checksum. The change that i did to the ttl is just a test to see that my checksum calc is ok). i compare the sys's , but didnt find and difference. Any idea? Ps. i saw this topic : Server not sending a SYN/ACK packet in response to a SYN packet and i set all flags the same , but this didnt help. Thank you

  Read the article

• WOL doesn't work if set to anything other than `a` but this setting makes it boot all the time

  - by Elton Carvalho

  I manage a small "cluster" of 4 Xeon machines with Intel boards in my lab. They are all plugged to a 5-port 3-Com switch with static IP addresses like 10.0.0.x. They are all running OpenSuse 11.4 and their /home/ is served by one of the machines (node00) via NFS. They are plugged to an UPS that can keep them on for ca. 15 minutes, but there are lots of electric shortages due to "unscheduled maintenace" that are longer than this. So they end up being powered down without notice. If I set the BIOS to turn them on after power shortages, the issue is that they all boot at the same time and, if node00 decides to run fsck in the /home/ partition, it does not finish booting before the others try to NFS mount their /home/. I am trying to make wake on lan work, so I can choose to boot the NFS clients only after the server has successfully booted. The problem is that when I run ethtool I get an output like this: Supports Wake-on: pumbag Wake-on: g Theoretically, it is set to wake on MagicPacket(tm), according to the manual. But sending the WOL packet using wol -i 10.0.0.255 $MACADDR does not wake up the box after I shut it down with halt. The ethernet link led blinks after I send the packet, so it appears to be getting to the machine. However, if I set it up with ethtool -s eth1 wol bag, the machine always wakes up right after halting, even if I don't send the Magic packet. This means that the device can wake up with LAN activity, but seems to be ignoring the magic packet. Setting wol ag does not wake the box with the MagicPacket. Does setting wol a mean that it should boot with any broadcast message? How can I diagnose the issue of the machine not waking up with the MagicPacket even though I am sending it and it's set up to wake up with it? Thanks in advance!

  Read the article

• Ubuntu 9.10 RSA authentication: ssh fails, filezilla runs fine

  - by MariusPontmercy

  This is quite a mistery for me. I usually use passwordless RSA authentication to login into my remote *nix servers with ssh and sftp. Never had any problem until now. I cannot connect to an Ubuntu 9.10 machine: user@myclient$ ssh -i .ssh/Ganymede_key [email protected] [...] debug1: Host 'ganymede.server.com' is known and matches the RSA host key. debug1: Found key in /home/user/.ssh/known_hosts:14 debug2: bits set: 494/1024 debug1: ssh_rsa_verify: signature correct debug2: kex_derive_keys debug2: set_newkeys: mode 1 debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug2: set_newkeys: mode 0 debug1: SSH2_MSG_NEWKEYS received debug1: SSH2_MSG_SERVICE_REQUEST sent debug2: service_accept: ssh-userauth debug1: SSH2_MSG_SERVICE_ACCEPT received debug2: key: .ssh/Ganymede_key (0xb96a0ef8) debug2: key: .ssh/Ganymede_key ((nil)) debug1: Authentications that can continue: publickey,password,keyboard-interactive debug1: Next authentication method: publickey debug1: Offering public key: .ssh/Ganymede_key debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,password,keyboard-interactive debug1: Trying private key: .ssh/Ganymede_key debug1: read PEM private key done: type RSA debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,password,keyboard-interactive debug2: we did not send a packet, disable method debug1: Next authentication method: keyboard-interactive debug2: userauth_kbdint debug2: we sent a keyboard-interactive packet, wait for reply debug2: input_userauth_info_req debug2: input_userauth_info_req: num_prompts 1 Then it falls back to password authentication. If I disable password authentication on the remote machine my connection attempt just fails with a "Permission denied (publickey)." state. Same thing for sftp from command line. The "funny" thing is that the exact same RSA key works like a charm with a Filezilla sftp session instead: 12:08:00 Trace: Offered public key from "/home/user/.filezilla/keys/Ganymede_key" 12:08:00 Trace: Offer of public key accepted, trying to authenticate using it. 12:08:01 Trace: Access granted 12:08:01 Trace: Opened channel for session 12:08:01 Trace: Started a shell/command 12:08:01 Status: Connected to ganymede.server.com 12:08:02 Trace: CSftpControlSocket::ConnectParseResponse() 12:08:02 Trace: CSftpControlSocket::ResetOperation(0) 12:08:02 Trace: CControlSocket::ResetOperation(0) 12:08:02 Status: Retrieving directory listing... 12:08:02 Trace: CSftpControlSocket::SendNextCommand() 12:08:02 Trace: CSftpControlSocket::ChangeDirSend() 12:08:02 Command: pwd 12:08:02 Response: Current directory is: "/root" 12:08:02 Trace: CSftpControlSocket::ResetOperation(0) 12:08:02 Trace: CControlSocket::ResetOperation(0) 12:08:02 Trace: CSftpControlSocket::ParseSubcommandResult(0) 12:08:02 Trace: CSftpControlSocket::ListSubcommandResult() 12:08:02 Trace: CSftpControlSocket::ResetOperation(0) 12:08:02 Trace: CControlSocket::ResetOperation(0) 12:08:02 Status: Directory listing successful Any thoughts? M

  Read the article

• TCP/UDP hole punching from and to the same NAT network

  - by Luc

  I was wondering if tcp/udp hole punching would still work when you are in the same network (behind a NAT), and what the packet's path would be. What happens when using hole punching on the same network, is that it will send a packet out with the same destination and source address. Only the source and destination port would differ. I imagine a router with NAT loopback enabled will handle this as it should, but how about other routers? Would they drop the packet, or would a router (the first?) from the ISP bounce the packet back after which it gets handled okay? I'm wondering because I was thinking about using this technique to circumvent a block between peers in a network (like a school network where clients can only access the internet, but any contact with each other is blocked). The only other option is to use a man in the middle as proxy (tunnel?). The disadvantage of this is that you have to have a server with significantly more bandwidth than one that would only do hole punching. Also the latency would increase significantly.

  Read the article

• cisco asa + action drop issue

  - by ghp

  Have created a tunnel between 10.x.y.z network and 122.a.b.c ..the tunnel is up and active, but when I try the packet tracer output ..I get the ACTION as drop. I have also enabled same-security-traffic permit intra-interface. Can someone help me what does this drop mean? Result: input-interface: inside input-status: up input-line-status: up output-interface: outside output-status: up output-line-status: up Action: drop Drop-reason: (acl-drop) Flow is denied by configured rule Packet Tracer output @Shane Madden: please find below the packet tracer output. CASA5K-A# CASA5K-A# config t CASA5K-A(config)# packet-tracer input inside tcp 10.x.y.112 0 122.a.b.c 0 Phase: 1 Type: ROUTE-LOOKUP Subtype: input Result: ALLOW Config: Additional Information: in 0.0.0.0 0.0.0.0 outside Phase: 2 Type: ACCESS-LIST Subtype: Result: DROP Config: Implicit Rule Additional Information: Result: input-interface: inside input-status: up input-line-status: up output-interface: outside output-status: up output-line-status: up Action: drop Drop-reason: (acl-drop) Flow is denied by configured rule CASA5K-A(config)# ======================================================================== The access-group are as follows : access-group acl-inbound in interface outside access-group acl-outbound in interface inside and the access-list's are access-list acl-inbound extended permit tcp any any gt 1023 access-list acl-outbound extended permit ip object-group net-Source object net-dest

  Read the article

• Exchange 2007 Email Error 451 4.7.0 Timeout waiting for client input

  - by HK1

  Our SBS 2008 server with Exchange 2007 started rejecting some (most) emails starting about 3 or 4 days ago. The return failure message looks something like this: The error that the other server returned was: 451 451 4.7.0 Timeout waiting for client input (state 18) I've rebooted our Sonicwall TZ-210 router and that doesn't make any difference. I think this problem has something to do with MTU (packet size) but I don't understand why the problem just started now. We haven't made any changes to our network infrastructure for weeks. If I ping our SonicWall (DSL connection, bridge mode) forcing unfragmented packets, I start getting packet dropouts at packet size 1320 or so. Maybe this is completely normal, I'm not sure. I haven't tried rebooting the DSL modem yet because I'm not on site. That's one of the next things I'll try.

  Read the article

• Openswan + xl2tpd connections time out after a while

  - by Halfgaar

  I have a non-NATed Openswan+xl2tpd server (Ubuntu 12.04), to which I connect with a Windows 8 behind NAT. The client loses its connection after a while of doing nothing (between 30 and 60 minutes, but I didn't time it). The client doesn't have enabled that it should kill inactive connections. Nor does it ever go into sleep mode. I also tried setting the kill-after-time to 24 hours, but that didn't help. The NAT router behind which the client located is Debian Linux, and its router is a Cisco which connects us directly to the data center where the server is. None of our other connections, like SSH, get dropped with inactivity (because of cheap routers). I did however try turning on the keepalives in /etc/ipsec.conf: config setup (...snip...) nat_traversal=yes force_keepalive=yes keep_alive=10 but that didn't help. As you can see in the config later, dead peer detection's action is clear. That would be a first suggestion to fix, but I need clear, because people will be connecting from everwhere but the kitchen sink. Besides, as I said, in the test setup I have now, I can't see any device killing its connection. (edit: 'restart' also has the same effect) These are of one time it happened: Jul 18 16:18:06 host xl2tpd[1918]: Maximum retries exceeded for tunnel 49070. Closing. Jul 18 16:18:06 host xl2tpd[1918]: Terminating pppd: sending TERM signal to pid 18359 Jul 18 16:18:06 host xl2tpd[1918]: Connection 4 closed to 89.188.x.y, port 1701 (Timeout) Jul 18 16:18:11 host xl2tpd[1918]: Unable to deliver closing message for tunnel 49070. Destroying anyway. and these on another: Jul 18 17:44:39 host xl2tpd[1918]: udp_xmit failed to 89.188.x.y:1701 with err=-1:Operation not permitted Jul 18 17:44:43 xl2tpd[1918]: last message repeated 4 times Jul 18 17:44:43 host xl2tpd[1918]: Maximum retries exceeded for tunnel 10918. Closing. Jul 18 17:44:43 host xl2tpd[1918]: udp_xmit failed to 89.188.x.y:1701 with err=-1:Operation not permitted Jul 18 17:44:43 host xl2tpd[1918]: Terminating pppd: sending TERM signal to pid 26338 Jul 18 17:44:43 host xl2tpd[1918]: Connection 6 closed to 89.188.x.y, port 1701 (Timeout) Jul 18 17:44:44 host xl2tpd[1918]: udp_xmit failed to 89.188.x.y:1701 with err=-1:Operation not permitted Jul 18 17:44:48 xl2tpd[1918]: last message repeated 3 times Jul 18 17:44:48 host xl2tpd[1918]: Unable to deliver closing message for tunnel 10918. Destroying anyway. Jul 18 17:44:59 host xl2tpd[1918]: Can not find tunnel 10918 (refhim=0) Jul 18 17:44:59 host xl2tpd[1918]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 10918 Dumping. Jul 18 17:45:09 host xl2tpd[1918]: Can not find tunnel 10918 (refhim=0) Jul 18 17:45:09 host xl2tpd[1918]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 10918 Dumping. Jul 18 17:45:19 host xl2tpd[1918]: Can not find tunnel 10918 (refhim=0) Jul 18 17:45:19 host xl2tpd[1918]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 10918 Dumping. Jul 18 17:45:29 host xl2tpd[1918]: Can not find tunnel 10918 (refhim=0) Jul 18 17:45:29 host xl2tpd[1918]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 10918 Dumping. Jul 18 17:45:39 host xl2tpd[1918]: Can not find tunnel 10918 (refhim=0) Jul 18 17:45:39 host xl2tpd[1918]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 10918 Dumping. Jul 18 17:45:49 host xl2tpd[1918]: Can not find tunnel 10918 (refhim=0) Jul 18 17:45:49 host xl2tpd[1918]: network_thread: unable to find call or tunnel to handle packet. call = 0, tunnel = 10918 Dumping. Versions: Ubuntu 12.04 Openswan: 2.6.37-1 xl2tpd: 3.1+dfsg-1 kernel: 3.2.0-49-generic configs: /etc/ipsec.conf: version 2.0 # conforms to second version of ipsec.conf specification config setup nat_traversal=yes virtual_private=%v4:10.0.0.0/8,%v4:192.168.0.0/16,%v4:172.16.0.0/12,%v4:!10.152.2.0/24 oe=off protostack=netkey force_keepalive=yes keep_alive=10 conn L2TP-PSK-NAT rightsubnet=vhost:%priv also=L2TP-PSK-noNAT conn L2TP-PSK-noNAT authby=secret pfs=no auto=add keyingtries=2 rekey=no dpddelay=30 dpdtimeout=120 dpdaction=clear ikelifetime=8h keylife=1h type=transport left=%defaultroute leftprotoport=17/1701 right=%any rightprotoport=17/%any /etc/xl2tpd/xl2tpd.conf [global] ipsec saref = no [lns default] ip range = 10.152.2.2-10.152.2.254 local ip = 10.152.2.1 refuse chap = yes refuse pap = yes require authentication = yes ppp debug = no pppoptfile = /etc/ppp/options.xl2tpd length bit = yes /etc/ppp/options.xl2tpd: require-mschap-v2 refuse-mschap ms-dns 10.152.2.1 asyncmap 0 auth crtscts idle 1800 mtu 1200 mru 1200 lock hide-password local #debug name l2tpd proxyarp lcp-echo-interval 30 lcp-echo-failure 4

  Read the article

• ssh through a bastion machine works on someone else's desktop but not my own

  - by Terrence Brannon

  I have to ssh into a bastion (jump) server in order to get to the final server. On the jump server, my .ssh/config says: Host * ForwardAgent yes My co-worker uses PuTTy and Pageant. When I use a putty shell to connect from his desktop to the final server as root via the jump server, it works fine. At my desk I cannot connect to the final server, only the jump server. However, if I go to his desk, and successfully log into the final server via the jump server, I can then go back to my desk and also do so.... but after a certain amount of time, my shells revert to the original behavior of not connecting to final server via jump server. The entire transcript of ssh -v -v -v final_server is here The relevant part to me is when the public key is offered but then it says 'we did not send a packet': debug1: Offering public key: /home/CORP/t.brannon/.ssh/id_dsa debug3: send_pubkey_test debug2: we sent a publickey packet, wait for reply debug1: Authentications that can continue: publickey,password debug2: we did not send a packet, disable method debug3: authmethod_lookup password

  Read the article

• Printing to shared printers across VPN

  - by CYMR0

  I have a program that prints labels at five remote sites. Two sites, aren't working, but the rest are with an identical (as far as I can tell) setup. Using Wireshark, I have determined that the handshaking all goes well, but after the "Open Print File Response" the packet that is sent from the server, doesn't reach the client. But I'm a bit at a loss as to where I go from here. I know the port the packet was sent on (445) isn't being blocked, the RST packet gets sent on the same port and that gets there fine. It's also weird that the three out of five sites are working fine. This has been up and running for years without issue, all that we have changed is our connectivity (from DSL to bonded DSL). But this traffic is over a VPN - so it can't be the ISP interfering either can it? I'm totally stuck, and any help would be much appreciated. Thanks!

  Read the article

• Is SYN flooding still a threat?

  - by Rob

  Well recently I've been reading about different Denial of Service methods. One method that kind of stuck out was SYN flooding. I'm a member of some not-so-nice forums, and someone was selling a python script that would DoS a server using SYN packets with a spoofed IP address. However, if you sent a SYN packet to a server, with a spoofed IP address, the target server would return the SYN/ACK packet to the host that was spoofed. In which case, wouldn't the spoofed host return an RST packet, thus negating the 75 second long-wait, and ultimately failing in its attempt to DoS the server?

  Read the article

• Windows 7 cannot join samba domain

  - by Antonis Christofides

  I have a 3.5.6 samba server with a LDAP backend (both on Debian 6.0). I've been successfully adding Windows XP machines to the domain for years. I now try to add Windows 7. I have made the recommended registry changes, but I don't have any success so far. Here is what happens: 1. I go to computer name, select "Domain" instead of "Workgroup", type in the domain name, click OK. It asks me for the username and password of an account that can add computers to the domain; I enter them. After about 40 seconds, I get the following message: The following error occurred attempting to join the domain "ITIA": The specified computer account could not be found. Contact an administrator to verify the account is in the domain. If the account has been deleted unjoin, reboot, and rejoin the domain. Despite this, the samba server successfully creates the computer account. 2. Therefore, if I try again a second time, without deleting the already created computer account, I get a different error: The following error occurred attempting to join the domain "ITIA": The specified account already exists. (Note that until a while ago samba wasn't configured to automatically create computer accounts. What I did whenever I wanted an XP to join was to manually create it. When I first attempted to solve the Windows 7 join problem, I setup samba to do this automatically, as this is what most people do, as I understand, and I thought that it might be related. I haven't attempted to add an XP since I made this change, so I don't know if it works, but whether it works or not, the problem remains.) Update 1: Here are the relevant parts of smb.conf: [global] panic action = /usr/share/samba/panic-action %d workgroup = ITIA server string = Itia file server announce as = NT interfaces = 147.102.160.1 volume = %h passdb backend = ldapsam:ldap://ldap.itia.ntua.gr:389 ldap admin dn = uid=samba,ou=daemons,dc=itia,dc=ntua,dc=gr ldap ssl = off ldap suffix = dc=itia,dc=ntua,dc=gr ldap user suffix = ou=people ldap group suffix = ou=groups ldap machine suffix = ou=computers unix password sync = no add machine script = smbldap-useradd -w -i %u log file = /var/log/samba/samba-log.all log level = 3 max log size = 5000 syslog = 2 socket options = SO_KEEPALIVE TCP_NODELAY encrypt passwords = true password level = 1 security = user domain master = yes local master = no wins support = yes domain logons = yes idmap gid = 1000-2000 Update 2: The server has a single network interface eth1 (also an unused eth0 that shows up only in the kernel boot messages) and two ip addresses; the main, 147.102.160.1, and an additional one, 147.102.160.37, that comes up with "ip addr add 147.102.160.37/32 dev eth1" (used only for a web site that has a different certificate than other web sites served from the same machine). One of the problems I recently faced was that samba was using the latter IP address. I fixed that by adding the "interfaces = 147.102.160.1" statement in smb.conf. Now: acheloos:/etc/apache2# tcpdump host 147.102.160.40 and not port 5900 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth1, link-type EN10MB (Ethernet), capture size 65535 bytes 13:13:56.549048 IP lithaios.itia.civil.ntua.gr.netbios-dgm > 147.102.160.255.netbios-dgm: NBT UDP PACKET(138) 13:13:56.549056 ARP, Request who-has acheloos2.itia.civil.ntua.gr tell lithaios.itia.civil.ntua.gr, length 46 13:13:56.549091 ARP, Reply acheloos2.itia.civil.ntua.gr is-at 00:10:4b:b4:9e:59 (oui Unknown), length 28 13:13:56.549324 IP acheloos.itia.civil.ntua.gr.netbios-dgm > lithaios.itia.civil.ntua.gr.netbios-dgm: NBT UDP PACKET(138) 13:13:56.549608 IP lithaios.itia.civil.ntua.gr.netbios-dgm > acheloos2.itia.civil.ntua.gr.netbios-dgm: NBT UDP PACKET(138) 13:13:56.549741 IP acheloos.itia.civil.ntua.gr.netbios-dgm > lithaios.itia.civil.ntua.gr.netbios-dgm: NBT UDP PACKET(138) 13:13:56.550364 IP lithaios.itia.civil.ntua.gr.netbios-dgm > acheloos.itia.civil.ntua.gr.netbios-dgm: NBT UDP PACKET(138) 13:13:56.550468 IP acheloos.itia.civil.ntua.gr.netbios-dgm > lithaios.itia.civil.ntua.gr.netbios-dgm: NBT UDP PACKET(138) (acheloos2 is the second IP address, 147.102.160.37). The above dump occurs when I click "OK" (to join the domain), until it asks me for the username and password of a user that can join the domain. I don't know why the client is contacting the second IP address. I tried temporarily deactivating it, but I still had some related ARP traffic (though I think not IP traffic).

  Read the article

• switch duplicates packets and forward in two route

  - by sami

  there is a network including a router, two hosts and a switch which connects hosts to router. i have a virtual machine on my system. the network adapter is set to act as bridge. so the virtual machine and real OS are my 2 hosts on different LAN. they use one network card and are connected to a switch. when each of host send a packet to the other one, the switch duplicate the packet and forward it to both router and the other host. how can I solve the duplicate packet problem? Thanks.

  Read the article

• Is there a suitable chain for iptables when eth is in Promisc mode?

  - by user1495181

  I have a fron-end machine. Machine have2 eth cards. I want to use netfilter queue to do some checks on the packets. I set eth like this: ifconfig eth0 0.0.0.0 promisc up ifconfig eth1 0.0.0.0 promisc up I want to have an iptable rule like this(only example): iptables -A INPUT -i eth0 -j LOG --log-prefix " eth0 packet " but the packet is no passed through the iptables ,because it dosnt target to this MAC. Promisc mode didnt help. I saw that there is a way to add iptables chain for PROMISC, but need compilation... Is there any simplier way to have iptables rule when packet is not target to this eth. Currently i bypass this by creating a bridge between 2 eth and put rule on the FORWARD, but i done want to create bridge.

  Read the article

• openfire cannot subscribe gmail user

  - by cometta

  i trying to add gmail user with my local openfire, but get error below. I think something wrong with dns srv. can anyone suggest how to troubleshoot? </error> </presence> at org.jivesoftware.openfire.spi.RoutingTableImpl.routePacket(RoutingTableImpl.java:217) at org.jivesoftware.openfire.server.OutgoingSessionPromise$PacketsProcessor.returnErrorToSender(OutgoingSessionPromise.java:285) at org.jivesoftware.openfire.server.OutgoingSessionPromise$PacketsProcessor.run(OutgoingSessionPromise.java:204) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:651) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:676) at java.lang.Thread.run(Thread.java:613) 2010.04.25 23:30:57 Error returning error to sender. Original packet: <presence id="lBI4K-24" to="[email protected]" type="subscribe" from="[email protected]"/> org.jivesoftware.openfire.PacketException: Cannot route packet of type IQ or Presence to bare JID: <presence id="lBI4K-24" to="[email protected]" from="[email protected]" type="error"> <error code="404" type="cancel"> <remote-server-not-found xmlns="urn:ietf:params:xml:ns:xmpp-stanzas"/> </error> </presence> at org.jivesoftware.openfire.spi.RoutingTableImpl.routePacket(RoutingTableImpl.java:217) at org.jivesoftware.openfire.server.OutgoingSessionPromise$PacketsProcessor.returnErrorToSender(OutgoingSessionPromise.java:285) at org.jivesoftware.openfire.server.OutgoingSessionPromise$PacketsProcessor.run(OutgoingSessionPromise.java:219) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:651) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:676) at java.lang.Thread.run(Thread.java:613) 2010.04.25 23:31:56 Error returning error to sender. Original packet: <presence id="gmEsS-26" to="[email protected]" type="subscribe" from="[email protected]"/> org.jivesoftware.openfire.PacketException: Cannot route packet of type IQ or Presence to bare JID: <presence id="gmEsS-26" to="[email protected]" from="[email protected]" type="error"> <error code="404" type="cancel"> <remote-server-not-found xmlns="urn:ietf:params:xml:ns:xmpp-stanzas"/> </error> </presence> at org.jivesoftware.openfire.spi.RoutingTableImpl.routePacket(RoutingTableImpl.java:217) at org.jivesoftware.openfire.server.OutgoingSessionPromise$PacketsProcessor.returnErrorToSender(OutgoingSessionPromise.java:285) at org.jivesoftware.openfire.server.OutgoingSessionPromise$PacketsProcessor.run(OutgoingSessionPromise.java:219) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:651) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:676) at java.lang.Thread.run(Thread.java:613) 2010.04.25 23:31:56 Error returning error to sender. Original packet: <presence id="gmEsS-27" to="[email protected]" type="subscribe" from="[email protected]"/> org.jivesoftware.openfire.PacketException: Cannot route packet of type IQ or Presence to bare JID: <presence id="gmEsS-27" to="[email protected]" from="[email protected]" type="error"> <error code="404" type="cancel"> <remote-server-not-found xmlns="urn:ietf:params:xml:ns:xmpp-stanzas"/> </error> </presence> at org.jivesoftware.openfire.spi.RoutingTableImpl.routePacket(RoutingTableImpl.java:217) at org.jivesoftware.openfire.server.OutgoingSessionPromise$PacketsProcessor.returnErrorToSender(OutgoingSessionPromise.java:285) at org.jivesoftware.openfire.server.OutgoingSessionPromise$PacketsProcessor.run(OutgoingSessionPromise.java:204) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:651) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:676) at java.lang.Thread.run(Thread.java:613)

  Read the article

• Traffic estimation for a multiplayer flash game

  - by Steve Addington

  hey, i want to know if my rough traffic estimations are right, it would be for a pretty simple realtime flashgame in the style of haxball (but not as a soccer game) heres a video of it http://www.youtube.com/watch?v=z_xBdFg1RcI So here comes my estimation, i dont know if they are realistic! i hope someone can help me. consider the packet attached as a typical one sent every 200ms, its 148bytes + 64 bytes of header will make around a 200bytes packet. The server will receive 200bytes x 6 players x 5 times a sec=6000bytes/s=5.85Kbytes/s=46.9kbit/s plus he has to send all back to the players, so at this point are 94Kbit/s.The server received all the information, perform the definitive calculation and send the new position to all players, in a bigger packet of around 900bytes that have to be delivered to the others 6, which makes 900bytes x 6 players x 5 times a sec=27000bytes/s=26Kbytes/s=210kbit/s. overall that would be 26kbyte per second. thats like 130mb traffic per hour for a 6player room. but somehow i think the numbers are too high? that would be really much traffic for such a simple game. did i calculate something wrong?

  Read the article

• Client side latency when using prediction

  - by Tips48

  I've implemented Client-Side prediction into my game, where when input is received by the client, it first sends it to the server and then acts upon it just as the server will, to reduce the appearance of lag. The problem is, the server is authoritative, so when the server sends back the position of the Entity to the client, it undo's the effect of the interpolation and creates a rubber-banding effect. For example: Client sends input to server - Client reacts on input - Server receives and reacts on input - Server sends back response - Client reaction is undone due to latency between server and client To solve this, I've decided to store the game state and input every tick in the client, and then when I receive a packet from the server, get the game state from when the packet was sent and simulate the game up to the current point. My questions: Won't this cause lag? If I'm receiving 20/30 EntityPositionPackets a second, that means I have to run 20-30 simulations of the game state. How do I sync the client and server tick? Currently, I'm sending the milli-second the packet was sent by the server, but I think it's adding too much complexity instead of just sending the tick. The problem with converting it to sending the tick is that I have no guarantee that the client and server are ticking at the same rate, for example if the client is an old-end PC.

  Read the article

• Ubuntu 12.04 connected to wireless network but internet not working

  - by A.J.

  I can connect to my house's wireless network just fine, but when I'm connected I can't browse the web. Firefox starts connecting to a site and then just poops out. This doesn't happen on my roommates' computers (running Windows) or on our 3DSes, so I know it's just my laptop. I already tried sudo dhclient -r sudo dhclient sudo ifconfig eth0 down sudo ifconfig eth0 up Results of a few commands I was asked to run in comments: ping -c 2 4.2.2.2 PING 4.2.2.2 (4.2.2.2) 56(84) bytes of data. ^C --- 4.2.2.2 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1007ms ping -c 2 google.com PING google.com (173.194.33.38) 56(84) bytes of data. --- google.com ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1006ms nm-tool NetworkManager Tool State: connected (global) - Device: eth0 ----------------------------------------------------------------- Type: Wired Driver: atl1c State: unavailable Default: no HW Address: 88:AE:1D:6B:4E:E7 Capabilities: Carrier Detect: yes Speed: 100 Mb/s Wired Properties Carrier: off - Device: wlan0 [JUSTICE] ----------------------------------------------------- Type: 802.11 WiFi Driver: ath9k State: connected Default: yes HW Address: 1C:65:9D:65:C6:31 Capabilities: Speed: 1 Mb/s Wireless Properties WEP Encryption: yes WPA Encryption: yes WPA2 Encryption: yes Wireless Access Points (* = current AP) HOME-9B18: Infra, 00:26:F3:53:9B:18, Freq 2412 MHz, Rate 54 Mb/s, Strength 34 WPA WPA2 cougdad48 Network: Infra, 60:33:4B:E4:C4:5D, Freq 2437 MHz, Rate 54 Mb/s, Strength 22 WPA2 cougdad48 Guest Network: Infra, 66:33:4B:E4:C4:5D, Freq 2437 MHz, Rate 54 Mb/s, Strength 20 WPA2 belkin.ade: Infra, 94:44:52:FF:8A:DE, Freq 2457 MHz, Rate 54 Mb/s, Strength 20 WPA WPA2 *JUSTICE: Infra, 00:24:01:7B:9F:7E, Freq 2462 MHz, Rate 54 Mb/s, Strength 88 WEP CenturyLink: Infra, B2:B2:DC:8E:E2:58, Freq 2462 MHz, Rate 54 Mb/s, Strength 17 WPA WPA2 IPv4 Settings: Address: 192.168.0.11 Prefix: 24 (255.255.255.0) Gateway: 192.168.0.1 DNS: 192.168.0.1 (JUSTICE is my home's network.) ping -c 2 198.168.0.1 PING 198.168.0.1 (198.168.0.1) 56(84) bytes of data. --- 198.168.0.1 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1007ms

  Read the article

• recent unreliable wireless connection on 10.04 and 10.10

  - by gabkdlly

  Recently, my internet connection over wireless has become unreliable, on both a Dell laptop running Ubuntu 10.04 as well as my Desktop running Ubuntu 10.10 . The problem does not seem to occur on a laptop running Windows Vista. The problem does not seem to occur on my Openmoko Freerunner ( running Android 1.5 ), though I hardly ever use this device to connect over WLAN, so the problem may have just slipped by. This problem does not seem to appear when I boot into Ubuntu 9.10 from a live CD ( more precisely, I was able to ping fu-berlin.de for an hour without any packet loss ). Under Ubuntu 10.10, I am experiencing about 33% packet loss. On my main Ubuntu Desktop, I have tried the following wireless devices: a Longshine PCI card ( an old device with an RTL8180L chip ) a D-Link DWL-510 PCI card ( this device threw warnings in dmesg ) a USB device from MSI ( US54EX ). Usually my wireless network shows up in the network manager with a normal signal strength, even when the connection speed is slow ( which happens often ) or the connection gets reset ( asking me to click connect to re-authenticate my wireless connection ). I have observed this problem with a Netgear KWGR614 Router ( with the manufacturers firmware ), as well as with a TP-LINK TL-WR741ND router running OpenWrt. Taking a look at my routers logs, I find many instances of the following line: Tuesday,04 Jan 2011 03:53:01 [TCP SYN Flood][Deny access policy matched, dropping packet] I know that the Netgear router is susceptible to denial of service attacks, as I have previously been able to disrupt its operation by putting an nmap scan into a while loop. I use WEP on the Netgear router and WPA on the TP-LINK to encrypt the wireless connections. Is it possible that someone is jamming my signal ?

  Read the article

• How do I make my multicast program work between computers on different networks?

  - by George

  I made a little chat applet using multicast. It works fine between computers on the same network, but fails if the computers are on different networks. Why is this? import java.io.*; import java.net.*; import java.awt.*; import java.awt.event.*; import javax.swing.*; public class ClientA extends JApplet implements ActionListener, Runnable { JTextField tf; JTextArea ta; MulticastSocket socket; InetAddress group; String name=""; public void start() { try { socket = new MulticastSocket(7777); group = InetAddress.getByName("233.0.0.1"); socket.joinGroup(group); socket.setTimeToLive(255); Thread th = new Thread(this); th.start(); name =JOptionPane.showInputDialog(null,"Please enter your name.","What is your name?",JOptionPane.PLAIN_MESSAGE); tf.grabFocus(); }catch(Exception e) {e.printStackTrace();} } public void init() { JPanel p = new JPanel(new BorderLayout()); ta = new JTextArea(); ta.setEditable(false); ta.setLineWrap(true); JScrollPane sp = new JScrollPane(ta); p.add(sp,BorderLayout.CENTER); JPanel p2 = new JPanel(); tf = new JTextField(30); tf.addActionListener(this); p2.add(tf); JButton b = new JButton("Send"); b.addActionListener(this); p2.add(b); p.add(p2,BorderLayout.SOUTH); add(p); } public void actionPerformed(ActionEvent ae) { String message = name+":"+tf.getText(); tf.setText(""); tf.grabFocus(); byte[] buf = message.getBytes(); DatagramPacket packet = new DatagramPacket(buf,buf.length, group,7777); try { socket.send(packet); } catch(Exception e) {} } public void run() { while(true) { byte[] buf = new byte[256]; String received = ""; DatagramPacket packet = new DatagramPacket(buf, buf.length); try { socket.receive(packet); received = new String(packet.getData()).trim(); } catch(Exception e) {} ta.append(received +"\n"); ta.setCaretPosition(ta.getDocument().getLength()); } } }

  Read the article

• Feedback on Optimizing C# NET Code Block

  - by Brett Powell

  I just spent quite a few hours reading up on TCP servers and my desired protocol I was trying to implement, and finally got everything working great. I noticed the code looks like absolute bollocks (is the the correct usage? Im not a brit) and would like some feedback on optimizing it, mostly for reuse and readability. The packet formats are always int, int, int, string, string. try { BinaryReader reader = new BinaryReader(clientStream); int packetsize = reader.ReadInt32(); int requestid = reader.ReadInt32(); int serverdata = reader.ReadInt32(); Console.WriteLine("Packet Size: {0} RequestID: {1} ServerData: {2}", packetsize, requestid, serverdata); List<byte> str = new List<byte>(); byte nextByte = reader.ReadByte(); while (nextByte != 0) { str.Add(nextByte); nextByte = reader.ReadByte(); } // Password Sent to be Authenticated string string1 = Encoding.UTF8.GetString(str.ToArray()); str.Clear(); nextByte = reader.ReadByte(); while (nextByte != 0) { str.Add(nextByte); nextByte = reader.ReadByte(); } // NULL string string string2 = Encoding.UTF8.GetString(str.ToArray()); Console.WriteLine("String1: {0} String2: {1}", string1, string2); // Reply to Authentication Request MemoryStream stream = new MemoryStream(); BinaryWriter writer = new BinaryWriter(stream); writer.Write((int)(1)); // Packet Size writer.Write((int)(requestid)); // Mirror RequestID if Authenticated, -1 if Failed byte[] buffer = stream.ToArray(); clientStream.Write(buffer, 0, buffer.Length); clientStream.Flush(); } I am going to be dealing with other packet types as well that are formatted the same (int/int/int/str/str), but different values. I could probably create a packet class, but this is a bit outside my scope of knowledge for how to apply it to this scenario. If it makes any difference, this is the Protocol I am implementing. http://developer.valvesoftware.com/wiki/Source_RCON_Protocol

  Read the article

< Previous Page | 14 15 16 17 18 19 20 21 22 23 24 25  | Next Page >