Search Results

Search found 1031 results on 42 pages for 'subnet'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 19/42 | < Previous Page | 15 16 17 18 19 20 21 22 23 24 25 26  | Next Page >

  • DHCP "no answer" on CentOS 6.4

    - by Kev
    I installed a DHCP server (yum install dhcp) and this is my conf: # create new # specify domain name option domain-name "mydomain.name"; # specify DNS's hostname or IP address option domain-name-servers 10.0.1.1, 10.0.1.2; option ntp-servers 10.0.1.1, 10.0.1.2; allow unknown-clients; # default lease time default-lease-time 2628000; # max lease time max-lease-time 2628000; # about a month # this DHCP server to be declared valid authoritative; # specify network address and subnet mask subnet 10.0.0.0 netmask 255.0.0.0 { # specify the range of lease IP address range dynamic-bootp 10.0.2.1 10.0.2.50; # specify broadcast address option broadcast-address 10.255.255.255; # specify default gateway option routers 10.0.0.1; allow unknown-clients; } service dhcp start reports [ OK ]. Yet, if I disable my other DHCP server (Win2k3) and get a client to try renewing its IP lease, it times out. So I installed dhcping. No matter what options I try, including directing dhcping at my server, adding a client address in the range, adding my hardware address, it replies 'no answer'. I'm also trying -i since that seems to be more akin to what a WinXP client would try to do, based on /var/log/messages. It logs the attempts (from dhcping here) as: Oct 24 18:55:13 newdc dhcpd: DHCPINFORM from 10.0.2.15 via eth0:4 Oct 24 18:55:13 newdc dhcpd: DHCPACK to 10.0.2.15 (00:11:25:66:4e:7f) via eth0:4 Oct 24 18:55:13 newdc dhcpd: DHCPINFORM from 10.0.2.15 via eth0:3 Oct 24 18:55:13 newdc dhcpd: DHCPACK to 10.0.2.15 (00:11:25:66:4e:7f) via eth0:3 Oct 24 18:55:13 newdc dhcpd: DHCPINFORM from 10.0.2.15 via eth0 Oct 24 18:55:13 newdc dhcpd: DHCPACK to 10.0.2.15 (00:11:25:66:4e:7f) via eth0 The :3 and :4 are because I have a few extra Host(A) records for this server so it responds on more than one IP for our intranet app. No answer? It sounds like it should be getting three answers...no? (And if that's the problem, how do I limit the DHCP service to replying from eth0?)

    Read the article

  • VPN iptables Forwarding: Net-to-net

    - by Mike Holler
    I've tried to look elsewhere on this site but I couldn't find anything matching this problem. Right now I have an ipsec tunnel open between our local network and a remote network. Currently, the local box running Openswan ipsec with the tunnel open can ping the remote ipsec box and any of the other computers in the remote network. When logged into on of the remote computers, I can ping any box in our local network. That's what works, this is what doesn't: I can't ping any of the remote computers via a local machine that is not the ipsec box. Here's a diagram of our network: [local ipsec box] ----------\ \ [arbitrary local computer] --[local gateway/router] -- [internet] -- [remote ipsec box] -- [arbitrary remote computer] The local ipsec box and the arbitrary local computer have no direct contact, instead they communicate through the gateway/router. The router has been set up to forward requests from local computers for the remote subnet to the ipsec box. This works. The problem is the ipsec box doesn't forward anything. Whenever an arbitrary local computer pings something on the remote subnet, this is the response: [user@localhost ~]# ping 172.16.53.12 PING 172.16.53.12 (172.16.53.12) 56(84) bytes of data. From 10.31.14.16 icmp_seq=1 Destination Host Prohibited From 10.31.14.16 icmp_seq=2 Destination Host Prohibited From 10.31.14.16 icmp_seq=3 Destination Host Prohibited Here's the traceroute: [root@localhost ~]# traceroute 172.16.53.12 traceroute to 172.16.53.12 (172.16.53.12), 30 hops max, 60 byte packets 1 router.address.net (10.31.14.1) 0.374 ms 0.566 ms 0.651 ms 2 10.31.14.16 (10.31.14.16) 2.068 ms 2.081 ms 2.100 ms 3 10.31.14.16 (10.31.14.16) 2.132 ms !X 2.272 ms !X 2.312 ms !X That's the IP for our ipsec box it's reaching, but it's not being forwarded. On the IPSec box I have enabled IP Forwarding in /etc/sysctl.conf net.ipv4.ip_forward = 1 And I have tried to set up IPTables to forward: *filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [759:71213] -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p icmp -j ACCEPT -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 25 -j ACCEPT -A INPUT -p udp -m state --state NEW -m udp --dport 500 -j ACCEPT -A INPUT -p udp -m state --state NEW -m udp --dport 4500 -j ACCEPT -A INPUT -m policy --dir in --pol ipsec -j ACCEPT -A INPUT -p esp -j ACCEPT -A INPUT -j REJECT --reject-with icmp-host-prohibited -A FORWARD -s 10.31.14.0/24 -d 172.16.53.0/24 -j ACCEPT -A FORWARD -m policy --dir in --pol ipsec -j ACCEPT -A FORWARD -j REJECT --reject-with icmp-host-prohibited COMMIT Am I missing a rule in IPTables? Is there something I forgot? NOTE: All the machines are running CentOS 6.x Edit: Note 2: eth1 is the only network interface on the local ipsec box.

    Read the article

  • Configuring VLAN's on two HP procurve switches

    - by pan
    Trying to route a new ISP (Microwave link) from one of my out buildings to my computer room and hence my firewall. Old ISP came direct into firewall. In the outbuilding the Microwave modem connects with cat5 to HP Procurve 2524 switch. Because this ISP is coming through my internal network, I plan on using a new vlan called "airspeed" only for this ISP traffic. Up until now I've just been using the Default_vlan on both HP switches (4108 + 2524). So far I've been unable to ping from my laptop to the ISP modem both of which are on the new vlan 2 ("Airspeed"). No traffic needs to cross from vlan 2 to vlan 1 so I've left the ports as untagged. I've used the subnet provide from my ISP as the new vlan 2 subnet. Can anybody see what I'm doing wrong here? I've added the configuration of both switch below. Rough diagram: Microwave modem (Gateway IP 77.75.00.49) | HP 2524 switch (port 24) | HP 2524 switch fibre link | HP 4108GL switch fibre link | HP 4108GL switch (port D1) | Laptop configured with IP 77.75.00.50 (for testing but will be connected to firewall) And my 4108GL config: ; J4865A Configuration Editor; Created on release #G.07.21 hostname "HP ProCurve Switch 4108GL" cdp run module 1 type J4864A module 2 type J4862B module 3 type J4862B module 4 type J4862B ip default-gateway 128.1.146.50 snmp-server community "public" Unrestricted snmp-server host 128.1.146.51 "public" Not-INFO snmp-server host 128.1.146.38 "public" vlan 1 name "DEFAULT_VLAN" untagged A1-A3,B1-B24,C1-C24,D2-D24 ip address 128.1.146.203 255.255.0.0 no untagged D1 exit vlan 2 name "Airspeed" untagged D1 ip address 77.75.00.51 255.255.255.248 exit Finally my 2524 config: ; J4813A Configuration Editor; Created on release #F.04.08 hostname "HP ProCurve Switch 2524" cdp run ip default-gateway 0.0.0.0 snmp-server community "public" Unrestricted snmp-server host 128.1.146.51 "public" Not-INFO snmp-server host 128.1.146.51 "public" snmp-server host 128.1.146.38 "public" vlan 1 name "DEFAULT_VLAN" untagged 1-23,25-26 no untagged 24 ip address 128.1.146.204 255.255.0.0 exit vlan 2 name "Airspeed" untagged 24 ip address 77.75.00.51 255.255.255.248 exit no aaa port-access authenticator active

    Read the article

  • dnsmasq acts as the DHCP server for selected nodes overriding the existing DHCP server on the same LAN?

    - by user183394
    I am trying to set up a small "lab" at home. Like many modern homes, I have a regular DSL service which comes with a 2Wire 3600HGV router, which acts also as a DHCP server. Since I would like to PXE boot a few computers in my "lab" The 2Wire is inflexible to adjustments that I want to do I have used dnsmasq at work so I would like to use dnsmasq as the DHCP server for the few nodes in my "lab" if feasible. In the dnsmasq man page, there is the following: [...] -K, --dhcp-authoritative (IPv4 only) Should be set when dnsmasq is definitely the only DHCP server on a network. It changes the behaviour from strict RFC compliance so that DHCP requests on unknown leases from unknown hosts are not ignored. This allows new hosts to get a lease without a tedious timeout under all circumstances. It also allows dnsmasq to rebuild its lease database without each client needing to reacquire a lease, if the database is lost. [...] As far as I know, the ISC DHCP server can use the following to do what I would like to accomplish: authoritative; [...] subnet 192.168.1.0 netmask 255.255.255.0 { host nb0 { # only give DHCP information to this computer: hardware ethernet e8:9a:8f:17:70:42; fixed-address 192.168.1.10; option subnet-mask 255.255.255.0; option routers 192.168.1.254; option domain-name-servers 192.168.1.254; # Non-essential DHCP options filename "/pxelinux.0"; } [...] But I much prefer dnsmasq's "all-in-one-ness". My question: do I have to couple the -K option with something else? As shown in the example above, the ISC DHCP server requires the mac addresses of managed nodes to be explicitly specified. Does dnsmasq have something similar? FYI, the machine on which I plan to run dnsmasq runs CentOS 6.3 64bit. It has a statically assigned IP address: 192.168.1.3.

    Read the article

  • Why is my router not routing?

    - by dwj
    Starting a week and half ago my router stopped working with my cable modem. I went to sleep with it working and woke up with it not. I swapped in another router and am still having issues; I was gone for 10 days so now I'm back to trying to figure it out. While I was gone I left everything (cable modem, router, and computer) powered off. My setup: Comcast Ambit cable modem (from Comcast) Netgear WGR614 v4 router -- replaced with Linksys WRT54GS v1.1 Windows XP SP3 other computers, all currently unplugged The modem is using the firmware (ver 2.105.2001) provided by Comcast; hardware version 1.3 The Linksys router is using FW ver 4.71.4 (latest for this release of HW), factory defaults I am only using the wired connections; no wireless. I have swapped out all of the cat5 cable. If I plug my computer directly into the cable modem, I can ping by name or number. Everything works perfectly. If I plug my computer into the router and the router into the modem, I cannot access anything outside of my local network. This is the exact setup I've used for the past 5 years; there were no changes in the past year. Now here's the interesting part: I can log into the Linksys router and get status information from it; everything appears good. Using the Diagnostics, I can run ping and traceroute to any site on the internet. These work perfectly. From my computer, I can ping the router and the modem. However, I cannot ping anything on the internet by with name or number. If I plug in another computer, I can ping it successfully. I've included two transcripts below that show these two attempts. Addresses, DNS, gateways, etc. look good. I cannot access the internet through either router. I am at a loss here. Suggestions? Help! Computer to Router to Cable Modem C:\ipconfig /renew Windows IP Configuration No operation can be performed on Bluetooth Network while it has its media disconnected. Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : hsd1.ca.comcast.net. IP Address. . . . . . . . . . . . : 192.168.1.100 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.1.1 Ethernet adapter Bluetooth Network: Media State . . . . . . . . . . . : Media disconnected C:\ipconfig /all Windows IP Configuration Host Name . . . . . . . . . . . . : wynton Primary Dns Suffix . . . . . . . : Node Type . . . . . . . . . . . . : Unknown IP Routing Enabled. . . . . . . . : No WINS Proxy Enabled. . . . . . . . : No DNS Suffix Search List. . . . . . : hsd1.ca.comcast.net. Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : hsd1.ca.comcast.net. Description . . . . . . . . . . . : Intel(R) 82562V-2 10/100 Network Connection Physical Address. . . . . . . . . : 00-1D-09-9B-45-EB Dhcp Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes IP Address. . . . . . . . . . . . : 192.168.1.100 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.1.1 DHCP Server . . . . . . . . . . . : 192.168.1.1 DNS Servers . . . . . . . . . . . : 68.87.76.178 68.87.78.130 Lease Obtained. . . . . . . . . . : Monday, March 22, 2010 10:21:55 PM Lease Expires . . . . . . . . . . : Tuesday, March 23, 2010 10:21:55 PM Ethernet adapter Bluetooth Network: Media State . . . . . . . . . . . : Media disconnected Description . . . . . . . . . . . : Bluetooth LAN Access Server Driver Physical Address. . . . . . . . . : 00-0A-3A-6F-68-41 C:\ping google.com Ping request could not find host google.com. Please check the name and try again . C:\ping 74.125.19.104 Pinging 74.125.19.104 with 32 bytes of data: Request timed out. Request timed out. Request timed out. Request timed out. Ping statistics for 74.125.19.104: Packets: Sent = 4, Received = 0, Lost = 4 (100% loss), C:\ Computer to Cable Modem Directly C:\ipconfig /renew Windows IP Configuration No operation can be performed on Bluetooth Network while it has its media disconnected. Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : hsd1.ca.comcast.net. IP Address. . . . . . . . . . . . : 71.204.149.195 Subnet Mask . . . . . . . . . . . : 255.255.252.0 Default Gateway . . . . . . . . . : 71.204.148.1 Ethernet adapter Bluetooth Network: Media State . . . . . . . . . . . : Media disconnected C:\ipconfig /all Windows IP Configuration Host Name . . . . . . . . . . . . : wynton Primary Dns Suffix . . . . . . . : Node Type . . . . . . . . . . . . : Unknown IP Routing Enabled. . . . . . . . : No WINS Proxy Enabled. . . . . . . . : No DNS Suffix Search List. . . . . . : hsd1.ca.comcast.net. Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : hsd1.ca.comcast.net. Description . . . . . . . . . . . : Intel(R) 82562V-2 10/100 Network Connection Physical Address. . . . . . . . . : 00-1D-09-9B-45-EB Dhcp Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes IP Address. . . . . . . . . . . . : 71.204.149.195 Subnet Mask . . . . . . . . . . . : 255.255.252.0 Default Gateway . . . . . . . . . : 71.204.148.1 DHCP Server . . . . . . . . . . . : 68.87.76.10 DNS Servers . . . . . . . . . . . : 68.87.76.178 68.87.78.130 Lease Obtained. . . . . . . . . . : Monday, March 22, 2010 10:18:50 PM Lease Expires . . . . . . . . . . : Monday, March 22, 2010 11:12:31 PM Ethernet adapter Bluetooth Network: Media State . . . . . . . . . . . : Media disconnected Description . . . . . . . . . . . : Bluetooth LAN Access Server Driver Physical Address. . . . . . . . . : 00-0A-3A-6F-68-41 C:\ping google.com Pinging google.com [74.125.19.99] with 32 bytes of data: Reply from 74.125.19.99: bytes=32 time=20ms TTL=55 Reply from 74.125.19.99: bytes=32 time=17ms TTL=55 Reply from 74.125.19.99: bytes=32 time=28ms TTL=55 Reply from 74.125.19.99: bytes=32 time=18ms TTL=55 Ping statistics for 74.125.19.99: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 17ms, Maximum = 28ms, Average = 20ms C:\ping 74.125.19.104 Pinging 74.125.19.104 with 32 bytes of data: Reply from 74.125.19.104: bytes=32 time=18ms TTL=55 Reply from 74.125.19.104: bytes=32 time=18ms TTL=55 Reply from 74.125.19.104: bytes=32 time=17ms TTL=55 Reply from 74.125.19.104: bytes=32 time=16ms TTL=55 Ping statistics for 74.125.19.104: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 16ms, Maximum = 18ms, Average = 17ms C:\

    Read the article

  • DHCP server with multiple interfaces on ubuntu, destroys default gateway

    - by Henrik Kjus Alstad
    I use Ubuntu, and I have many interfaces. eth0, which is my internet connection, and it gets its info from a DHCP-server totally outisde of my control. I then have eth1,eth2,eth3 and eth4 which I have created a DHCP-server for.(ISC DHCP-Server) It seems to work, and I even get an IP-address from the foreign DHCP-server on the internet facing interface. However, for some reason it seems my gateway for eth0 became screwed after I installed my local DHCP-server for eth1-eth4. (I think so because I got an IP for eth0, and I can ping other stuff on the local network, but I cannot get access to the internet). My eth0-specific info in /etc/network/interfaces: auto lo iface lo inet loopback auto eth0 iface eth0 inet dhcp auto eth1 iface eth1 inet static address 10.0.1.1 netmask 255.255.255.0 network 10.0.1.0 broadcast 10.0.1.255 gateway 10.0.1.1 mtu 8192 auto eth2 iface eth2 inet static address 10.0.2.1 netmask 255.255.255.0 network 10.0.2.0 broadcast 10.0.2.255 gateway 10.0.2.1 mtu 8192 My /etc/default/isc-dhcp-server: INTERFACES="eth1 eth2 eth3 eth4" So why does my local DHCP-server fuck up the gateway for eth0, when I tell it not to listen to eth0? Anyone see the problem or what I can do to fix it? The problem seems indeed to be the gateways. "netstat -nr" gives: 0.0.0.0 --- 10.X.X.X ---- 0.0.0.0 --- UG 0 0 0 eth3 It should have been 0.0.0.0 129.2XX.X.X 0.0.0.0 UG 0 0 0 eth0 So for some reason, my local DHCP-server overrides the gateway I get from the network DHCP. Edit: dhcp.conf looks like this(I included info only for eth1 subnet): ddns-update-style none; not authoritative; subnet 10.0.1.0 netmask 255.255.255.0 { interface eth1; option domain-name "example.org"; option domain-name-servers ns1.example.org, ns2.example.org; default-lease-time 600; max-lease-time 7200; range 10.0.1.10 10.0.1.100; host camera1_1 { hardware ethernet 00:30:53:11:24:6E; fixed-address 10.0.1.10; } host camera2_1 { hardware ethernet 00:30:53:10:16:70; fixed-address 10.0.1.11; } } Also, it seems that the gateway is correctly set if I run "/etc/init.d/networking restart" in a terminal, but that's not helpful for me, I need the correct gateway to be set during startup, and i'd rather find the source of the problem

    Read the article

  • any good networking book recommended? [closed]

    - by Jian Lin
    i have wanted to learn about networking and how they work. Are there books or websites that are good for them? Some things I wanted to learn about: how to write a program that works like traceroute / tracert how subnet masks work how http://192.168.1.105 works how http://127.0.0.1 works how http://localhost works how http://room3pc works how smb://room3pc works how a LAN works with or without DHCP how to connect to a mac using a URL

    Read the article

  • Can't connect to workgroup

    - by Bonyfus Martin
    I have two computers in my workgroup. My laptop has Windows 7 on it and desktop has Windows Server 2008 on it. I can ping and connect to the Windows Server 2008 from my laptop but I cannot ping or connect to my laptop from Windows Server 2008. Both computers are in the same workgroup, and their IP addresses use the same subnet mask. Does anyone know why I cannot connect to my laptop from the Windows Server 2008 machine?

    Read the article

  • How does NMap decide to print a progress line?

    - by Andrew Bolster
    Checking a larger subnet than I normally do; mapping out a cluster suite in a university for a traffic mapping project (permission attained), and I was wondering something. NMap usually prints its progress periodically, but I'm unclear to what that 'periodically' is, because the cirrent scan printed a line for basically every 100th of a percent up to 1% done, then one at 1.5%, and has said nothing since. I suspect that it changes at different 'levels' but does anyone have an actual answer?

    Read the article

  • VLSM, Rip V1 and Rip V2

    - by uBlankText
    I am trying to understand some things about Rip V1 and V2 but i am not sure if i am right, As i know Rip V1 doesn't "advertise" subnet masks, and doesn't support VLSM. If i understand right Even if Rip V1 for example supports VLSM it doesn't matter, Becouse the Rip V1 Only "advertise" the IP address, If some one can please confirm/expand/correct me I will be very thankful, Thank you all and have a nice day.

    Read the article

  • VMWare fusion cant get IP

    - by Mark Sutton
    Whenever I start my VM (Server 2003) it fails to pick up an IP address. It doesnt matter whether bridged or host and affects more than one image. If I set a static iP in the image on the same subnet as the host I cant ping anything on the network. Any ideas?

    Read the article

  • Multiple network connections on a Windows 2008 domain controller (private network for NAS)

    - by Sysadminicus
    I have a Windows 2008 server connecting to an iSCSI target on an OpenSolaris box (yay ZFS!). I'd like to create a private network between the 2 boxes that is totally separate of my Windows domain. What is the best way to configure the additional network adapter on the Windows machine so it doesn't think the new subnet is part of the Windows domain? I want to make sure Windows doesn't magically start spewing active directory communications over the private wire and that it doesn't start poisoning the DNS with IPs from the private network.

    Read the article

  • OpenVPN/Tunnelblick through wireless router, no connection.

    - by Oscar
    I'm using OpenVPN with Tunneblick on my Macbook Pro to access a server on my job. I't works fine, but i can't get it working with my Netgear WGT624v3 wireless router. I get this warning: WARNING: potential route subnet conflict between local LAN [192.168.1.0/255.255.255.0] and remote VPN [192.168.1.0/255.255.255.0] Someone told me that i should "port forward" on my router, but i can't figure out the right settings. Also not shure i'm doing it right.

    Read the article

  • Macintosh computers cannot connect to router unless we re-start the modem and router

    - by dwwilson66
    We have a small office network with DSL and a Netgear WNR-2000 wireless router acting as a DHCP server. There are nine devices connected to the router, wirelessly and wired. Whenever a Mac computer tries to connect, it's unsuccessful until we restart the router. Each of the possible devices that can connect to the network is listed in a table to assign certain IP addresses to certain MAC addresses. I am running WPA-PSK security. I can view the router status and see that the Mac's MAC address is visible to the router, but with a 169.* IP address, even though I'm assigning its MAC address to an IP address within my subnet. All non-Mac devices attached to the network connect properly, and can access the network properly even AFTER the Mac has not successfully connected. The network includes Windows devices, Roku boxes, printers and internet ready TVs. This to me, would point to a DHCP issue with how Mac communicates with my network. One interesting thing to note is that if a Mac connects and is prevented from sleeping, it will stay connected indefinitely; reissuing the security cert from the router works fine. I'm not sure if that's supposed to sever & re-establish a connection with the updated credentials or not, but I do stay connected. If the Mac sleeps and is awakened while the security cert is still valid, it connects fine. If the security certificate expires while the Mac is asleep, we need to restart the router. Restarting the router will ALWAYS assigns the proper IP addresses to the Mac equipment. I have heard anecdotally that Mac doesn't play well with 802.11n; I have not tested any other Wireless protocols. There's a couple issues here: First, I found this on Stack, Mac laptop crashing wireless router, but it's not rally applicable since the router isn't crashing. But, it does give some clues about Mac's accessing the network. I did change my encryption from WEP to WPA-PSK, but after about a week, we're still experiencing the issue. I'm not really sure if there's anything else useful in that question. Second, I'm considering getting a 802.11c router and hooking it up to the wireless N router. the 802.11c router would handle all the Mac traffic, and would be set up as a Mac-only subnet. Everything else would remain as is. However, I'm not sure if this is doable on a technology level...do I need a bridge or is this some way to do this with regular consumer gear?

    Read the article

  • Windows 2008 running as KVM guest networking issue

    - by Evolver
    I have a strange networking problem with Windows 2008 server R2, running as guest under KVM-Qemu host. Host is CentOS 6.3 x86_64. It's network settings: # cat /etc/sysconfig/network-scripts/ifcfg-br0 DEVICE=br0 BOOTPROTO=static BROADCAST=xx.xx.xx.63 IPADDR=xx.xx.xx.4 NETMASK=255.255.255.192 NETWORK=xx.xx.xx.0 ONBOOT=yes TYPE=Bridge # cat /etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE=eth0 HWADDR=xx:xx:xx:xx:xx:xx ONBOOT=yes BRIDGE=br0 IPV6INIT=yes IPV6_AUTOCONF=yes # cat /etc/sysconfig/network NETWORKING=yes NETWORKING_IPV6=no HOSTNAME=my.hostname GATEWAY=xx.xx.xx.1 # cat /etc/sysctl net.ipv4.ip_forward = 1 # tried to set it to 0 without any changes net.ipv4.conf.default.rp_filter = 1 # tried to set it to 0 without any changes net.ipv4.conf.default.accept_source_route = 0 # tried to set it to 1 without any changes kernel.sysrq = 0 kernel.core_uses_pid = 1 net.ipv4.tcp_syncookies = 1 net.bridge.bridge-nf-call-ip6tables = 0 net.bridge.bridge-nf-call-iptables = 0 net.bridge.bridge-nf-call-arptables = 0 kernel.msgmnb = 65536 kernel.msgmax = 65536 kernel.shmmax = 68719476736 kernel.shmall = 4294967296 # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface xx.xx.xx.0 0.0.0.0 255.255.255.192 U 0 0 0 br0 169.254.0.0 0.0.0.0 255.255.0.0 U 1004 0 0 br0 0.0.0.0 xx.xx.xx.1 0.0.0.0 UG 0 0 0 br0 Node IP is xx.xx.xx.4, guest IP is xx.xx.xx.24, both host and guest is in the same network (/26). There are several linux guest running fine on the node (centos, debian, ubuntu, arch), and even Windows 2003 x86 also running fine. But Win2008 does not. I wonder, what's the difference. From Win2008 guest I can ping nothing: neither gateway, nor any other IP, even they are in the same subnet. From outside I also cannot ping guest. Almost. If I ping it from another server in same subnet, it's barely pinging, losing more than 90% packets. Firewall on the guest is completely off. Tried to set up network manually as well as via DHCP without success (BTW, DHCP set up network settings correctly). I suspect that is a kind of routing problem, but I spent whole day and still cannot figure it out. I would be appreciate for any help.

    Read the article

  • Arp tries on various *nix based systems.

    - by salparadise
    Does anyone know what determines the amount of arp tries a router will make? I have different behaviors with two devices, if I try to traceroute to a non-existent host on a subnet that belongs to an interface on the router, a Linux box will try to arp 3 times and then return a host un-reacheable icmp message. Junos will continuosly try to arp and not return anything. Is there a sysctl value that determines this or anything at all.

    Read the article

  • How to run a DHCP service on Windows 7 Home

    - by Joshua Lim
    I'm trying to setup a DHCP server on Windows 7 Home, tried using a couple of freeware which I found on the Internet but none seemed to work. What I did: On the Windows 7 machine which I install the DHCP Server with the range 192.168.1.12-192.168.1.256. I set the Gigabit Ethernet adapter to a static IP address of 192.168.1.11 and subnet mask of 255.255.255.0. When I did an IP config, it showed. Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Broadcom NetLink (TM) Gigabit Ethernet Physical Address. . . . . . . . . : 8C-73-6E-75-A7-56 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : fe80::196d:b6bb:8f93:2555%12(Preferred) IPv4 Address. . . . . . . . . . . : 192.168.1.11(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1 fec0:0:0:ffff::2%1 fec0:0:0:ffff::3%1 NetBIOS over Tcpip. . . . . . . . : Enabled I connected another Window 7 machine to the "DHCP server" using a cross cable and set network adapter on that machine to automatically detect IP address. The client fails to acquire the correct IP address from the DHCP server and showed the autoconfigured IPv4 address instead. Here's the information returned by config /all on the client machine. Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Atheros AR8152/8158 PCI-E Fast Ethernet Controller (NDIS 6.20) Physical Address. . . . . . . . . : 54-04-A6-40-96-4B DHCP Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : fe80::4885:4082:5572:5a85%12(Preferred) Autoconfiguration IPv4 Address. . : 169.254.90.133(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.0.0 Default Gateway . . . . . . . . . : DHCPv6 IAID . . . . . . . . . . . : 341050534 DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-17-54-78-12-00-08-CA-46-4C-5A DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1 fec0:0:0:ffff::2%1 fec0:0:0:ffff::3%1 NetBIOS over Tcpip. . . . . . . . : Enabled DHCP client are running on both machines. I've tried many times but failed. Googling also returned no useful information for my scenario. Have I missed out any step? Thanks.

    Read the article

  • ISC DHCP - Force clients to get a new IP address, instead of the being re-issued their previous lease's IP

    - by kce
    We are in the middle of a migration of our DHCP and DNS services from a Debian-based server to a Windows Server 2008 R2 implementation. The Debian server is running isc-dhcpd-V3.1.1. All of workstations are configured to have fixed-addresses between .3 and .40 (the motivation behind that choice is mostly management/political much like here). DHCP leases are given out in the range of .100 to .175. Statically configured servers live in the .200 block and above (which is mostly empty). When we move to the Windows platform, management/political considerations require me to move the IP ranges around again. We would like to keep .1 - .10 reserved for network appliances, switches, and other infrastructure. .200 will remain designated for servers. The addressing space in between should be available to clients and IPs should be dynamically allocated (Edit: instead of automatic as originally mentioned) by the server. My Address Pool on the Windows Server looks like this: 192.168.0.1 192.168.0.254 (Address range for distribution) 192.168.0.1 192.168.0.10 (IP addresses excluded from distribution) 192.168.0.200 192.168.0.254 (IP addresses excluded from distribution) Currently, we have all of our clients still on the .3 - .40 range, and a few machines still active in the .100 - .175 (although there are lots devices that are powered off that still have expired leases with IPs from that range). Since the lease "database" isn't shared between the old and new DHCP server how can I prevent clients from receiving a lease with an IP address that is currently being held by client with a non-expired lease from the old DHCP server? If I just expand the range on the Debian DHCP server to be 192.168.0.10 - 192.168.0.199 is there a way to force clients to not re-use their old IP address when they send their DHCPDISCOVER? Can I make the Windows DHCP server be authoritiative like the ISC implementation? The dhcpd.conf from the Debian server: ddns-update-style none; authoritative; default-lease-time 43200; #12 hours max-lease-time 86400; #24 hours subnet 192.168.0.0 netmask 255.255.255.0 { option routers 192.168.0.1; option subnet-mask 255.255.255.0; option broadcast-address 192.168.0.255; range 192.168.0.100 192.168.0.175; } host workstation-1 { hardware ethernet 00:11:22:33:44:55; fixed-address 192.168.0.3; } ... and so on until 192.168.0.40

    Read the article

  • Why do ICMP Redirct Host happen?

    - by El Barto
    I'm setting up a Debian box as a router for 4 subnets. For that I have defined 4 virtual interfaces on the NIC where the LAN is connected (eth1). eth1 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.1.1 Bcast:10.1.1.255 Mask:255.255.255.0 inet6 addr: fe80::960c:6dff:fe82:d98/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:6026521 errors:0 dropped:0 overruns:0 frame:0 TX packets:35331299 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:673201397 (642.0 MiB) TX bytes:177276932 (169.0 MiB) Interrupt:19 Base address:0x6000 eth1:0 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.2.1 Bcast:10.1.2.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth1:1 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.3.1 Bcast:10.1.3.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth1:2 Link encap:Ethernet HWaddr 94:0c:6d:82:0d:98 inet addr:10.1.4.1 Bcast:10.1.4.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:19 Base address:0x6000 eth2 Link encap:Ethernet HWaddr 6c:f0:49:a4:47:38 inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::6ef0:49ff:fea4:4738/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:199809345 errors:0 dropped:0 overruns:0 frame:0 TX packets:158362936 errors:0 dropped:0 overruns:0 carrier:1 collisions:0 txqueuelen:1000 RX bytes:3656983762 (3.4 GiB) TX bytes:1715848473 (1.5 GiB) Interrupt:27 eth3 Link encap:Ethernet HWaddr 94:0c:6d:82:c8:72 inet addr:192.168.2.5 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::960c:6dff:fe82:c872/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:110814 errors:0 dropped:0 overruns:0 frame:0 TX packets:73386 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:16044901 (15.3 MiB) TX bytes:42125647 (40.1 MiB) Interrupt:20 Base address:0x2000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:22351 errors:0 dropped:0 overruns:0 frame:0 TX packets:22351 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2625143 (2.5 MiB) TX bytes:2625143 (2.5 MiB) tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 inet addr:10.8.0.1 P-t-P:10.8.0.2 Mask:255.255.255.255 UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1 RX packets:41358924 errors:0 dropped:0 overruns:0 frame:0 TX packets:23116350 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:3065505744 (2.8 GiB) TX bytes:1324358330 (1.2 GiB) I have two other computers connected to this network. One has IP 10.1.1.12 (subnet mask 255.255.255.0) and the other one 10.1.2.20 (subnet mask 255.255.255.0). I want to be able to reach 10.1.1.12 from 10.1.2.20. Since packet forwarding is enabled in the router and the policy of the FORWARD chain is ACCEPT (and there are no other rules), I understand that there should be no problem to ping from 10.1.2.20 to 10.1.1.12 going through the router. However, this is what I get: $ ping -c15 10.1.1.12 PING 10.1.1.12 (10.1.1.12): 56 data bytes Request timeout for icmp_seq 0 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 81d4 0 0000 3f 01 e2b3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 1 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 899b 0 0000 3f 01 daec 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 2 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 78fe 0 0000 3f 01 eb89 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 3 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 14b8 0 0000 3f 01 4fd0 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 4 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 8ef7 0 0000 3f 01 d590 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 5 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 ec9d 0 0000 3f 01 77ea 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 6 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 70e6 0 0000 3f 01 f3a1 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 7 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 b0d2 0 0000 3f 01 b3b5 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 8 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 f8b4 0 0000 3f 01 6bd3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 9 Request timeout for icmp_seq 10 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 1c95 0 0000 3f 01 47f3 10.1.2.20 10.1.1.12 Request timeout for icmp_seq 11 Request timeout for icmp_seq 12 Request timeout for icmp_seq 13 92 bytes from router2.mydomain.com (10.1.2.1): Redirect Host(New addr: 10.1.1.12) Vr HL TOS Len ID Flg off TTL Pro cks Src Dst 4 5 00 0054 62bc 0 0000 3f 01 01cc 10.1.2.20 10.1.1.12 Why does this happen? From what I've read the Redirect Host response has something to do with the fact that the two hosts are in the same network and there being a shorter route (or so I understood). They are in fact in the same physical network, but why would there be a better route if they are not on the same subnet (they can't see each other)? What am I missing? Some extra info you might want to see: # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.8.0.2 0.0.0.0 255.255.255.255 UH 0 0 0 tun0 127.0.0.1 0.0.0.0 255.255.255.255 UH 0 0 0 lo 192.168.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth3 10.8.0.0 10.8.0.2 255.255.255.0 UG 0 0 0 tun0 192.168.1.0 0.0.0.0 255.255.255.0 U 1 0 0 eth2 10.1.4.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.1.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth2 0.0.0.0 192.168.2.1 0.0.0.0 UG 100 0 0 eth3 # iptables -L -n Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination # iptables -L -n -t nat Chain PREROUTING (policy ACCEPT) target prot opt source destination Chain POSTROUTING (policy ACCEPT) target prot opt source destination MASQUERADE all -- !10.0.0.0/8 10.0.0.0/8 MASQUERADE all -- 10.0.0.0/8 !10.0.0.0/8 Chain OUTPUT (policy ACCEPT) target prot opt source destination

    Read the article

  • Microsoft VirtualPC Networking Issue

    - by Joda Maki
    I am using Microsoft VPC running the supplied microsoft images to test IE6/7. The ip addresses that get assigned to these images are via dhcp and get valid ip addresses in my subnet. They can access the external internet just fine. However, they cannot ping my host machine, nor can my host machine ping them (using internal ip addresses). Thus, they can't access my webserver to test with. How is this possible and how do I fix it?

    Read the article

  • Can't connect to EC2 instance in VPC (Amazon AWS)

    - by Ryan Lynch
    I've taken the following steps: Created a VPC (with a single public subnet) Added an EC2 instance to the VPC Allocated an elastic IP Associated the elastic IP with the instance Created a security group and assigned it to the instance Modified the security rules to allow inbound ICMP echo and TCP on port 22 I've done all this and I still can't ping or ssh into the instance. If I follow the same steps minus the VPC bits I am able to set this up without issue. What step am I missing?

    Read the article

  • Can't get DHCPd to assign IPs to unknown clients

    - by Jakobud
    I'm using Webmin to admin our DHCPd server. But I'm having a hard time getting it to assign IP addresses to unknown clients. The only way I can get it to assign an IP is to make sure a host is added to DHCPd as a host so that it gets a static-lease IP assigned to it. I thought "Allow Unknown Clients" was the key, but it still isn't assigning IPs to unknown clients. I have a pool setup so that the unknown clients should get an IP between 10.20.0.200 - 10.20.0.249. Here is the config file. What am I missing here? allow unknown-clients; # Primary DHCP server config authoritative; ddns-update-style none; failover peer "dhcp-failover" { primary; address 10.20.0.30; port 647; peer address 10.20.0.25; peer port 647; max-response-delay 60; max-unacked-updates 10; load balance max seconds 3; mclt 3600; split 128; } subnet 10.20.0.0 netmask 255.255.255.0 { allow unknown-clients; option subnet-mask 255.255.255.0; option broadcast-address 10.20.0.255; option routers 10.20.0.100; option domain-name "ourdomain.com"; option domain-name-servers 192.168.10.20; default-lease-time 86400; max-lease-time 86400; option ntp-servers 192.168.10.20; option time-offset -25200; pool { allow unknown-clients; failover peer "dhcp-failover"; max-lease-time 86400; range 10.20.0.200 10.20.0.249; deny dynamic bootp clients; } host Server-myserver { option host-name "whatever.ourdomain.com"; hardware ethernet 00:89:D4:35:4F:13; fixed-address 10.20.0.23; } }

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 15 16 17 18 19 20 21 22 23 24 25 26  | Next Page >