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I am currently trying to setup LAN over two machines with a network mask of 255.255.255.0 however I am receiving the following message when trying to communicate between them both;

[root@alpha ~]# ping 192.168.0.249
PING 192.168.0.249 (192.168.0.249) 56(84) bytes of data.
From 192.168.0.248 icmp_seq=2 Destination Host Unreachable
From 192.168.0.248 icmp_seq=3 Destination Host Unreachable
From 192.168.0.248 icmp_seq=4 Destination Host Unreachable
--- 192.168.0.249 ping statistics ---
6 packets transmitted, 0 received, +3 errors, 100% packet loss, time 5175ms

This happens vice versa on the other dedicated machine as well. I am clueless as to what I did wrong, I've rebooted & restarted the network service multiple times and still have no luck.

As you can see from below, ARP returns no LAN addresses however it should display the two. IPTables is disabled and the regular public IP will allow pings.

Details for Dedi #1:

[root@alpha ~]# ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:25:90:C8:81:4C
          inet addr:192.168.0.248  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::225:90ff:fec8:814c/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:3634 errors:0 dropped:0 overruns:0 frame:0
          TX packets:197 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:220672 (215.5 KiB)  TX bytes:10318 (10.0 KiB)
          Memory:f7180000-f7200000

[root@alpha ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
*.*.*.152       0.0.0.0         255.255.255.248 U     0      0        0 eth1
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1003   0        0 eth1
0.0.0.0         *.*.*.153       0.0.0.0         UG    0      0        0 eth1
[root@alpha ~]# arp -a
? (*.*.*.153) at 74:8e:f8:f7:98:58 [ether] on eth1

Details for Dedi #2:

[root@beta network-scripts]# ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:25:90:C5:C8:A0
          inet addr:192.168.0.249  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::225:90ff:fec5:c8a0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:54 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:3576 (3.4 KiB)
          Memory:f7180000-f7200000

[root@beta network-scripts]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
*.*.*.128       0.0.0.0         255.255.255.248 U     0      0        0 eth1
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1003   0        0 eth1
0.0.0.0         *.*.*.129       0.0.0.0         UG    0      0        0 eth1
[root@beta network-scripts]# arp -a
? (*.*.*.129) at 74:8e:f8:fa:b9:8e [ether] on eth1
share|improve this question
    
And you checked the obvious, that both NICs on each system are cabled and connected to the correct switch (-ports)? –  HBruijn Apr 8 at 12:39
    
Yes, both cards are connected to the correct switch and ports. –  Mhmk Apr 8 at 12:45
    
Does ethtool show the link as being up? Is the switch managed and do the MAC addresses show up? Correct VLAN assigned? –  HBruijn Apr 8 at 13:12
    
Yes, it shows them as link detected. I haven't got physical access to the switch as the servers are hosted with SecuredServers. –  Mhmk Apr 8 at 13:17
    
I'd bet there's a VLAN or ACL preventing those switch ports communicating. –  NickW Apr 8 at 13:24

1 Answer 1

up vote 0 down vote accepted

While I'm not 100% sure (you'd have to contact SecureServers), most hosting companies isolate servers that are on the same switch with a VLAN or ACL entry. In this way, your servers cannot see each other.

Contact your hosting company to be sure. Most likely they'll have to either set up a dedicated "internal" network for you or you'll need to use a VPN solution.

share|improve this answer
    
Just contacted them and they told me that they need to perform some changes to the VLAN! Thanks, Nathan. –  Mhmk Apr 8 at 14:12

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