CentOS - Oct 2010 - network interface up but no data

Hi List,

I am running a x86_64 Centos server, after a reboot the network has decided to
not work.. this particular machine has 8 eth ports eth0-7. eth0 and eth3 were
bonded (mode 1 ) after reboot the bond did not work. It came up OK but no
data was passing through it. all other interfaces on the machine were working.

I decided to remove the bond, so after removing the bond i was left with eth0
using the same IP as the bond used. however it still does the same thing,
it starts up with no errors but i cannot even ping the default gateway,
tcpdump shows nothing on the interface.

I have made sure of the following
* no iptables installed
* kernel modules for the NIC are loaded with no errors
* the bond kernel module is not installed / all bond configs have been removed

Below is some info on the interface, it should be noted that all others are OK
the only 2 that were having the issue are eth0 and eth3 (the ex-bonded ones)

server1:/etc/sysconfig/network-scripts# ip route  | grep 172.18
172.18.16.0/24 dev eth0  proto kernel  scope link  src 172.18.16.1
default via 172.18.16.254 dev eth0


# ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:24:49:C8:66:98
          inet addr:172.18.16.1  Bcast:172.18.16.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:7223 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:463918 (453.0 KiB)
          Interrupt:226 Memory:dc000000-dc012800


If you look closely TX  and RX are massively different, but I am not
seeing anything on tcpdump even there is a large number of TX packets.

Any ideas?

Nathan

On Thu, Oct 21, 2010 at 9:52 PM, Nat N <phenisha at gmail.com>
wrote:
> Hi List,
>
> I am running a x86_64 Centos server, after a reboot the network has decided
to
> not work.. this particular machine has 8 eth ports eth0-7. eth0 and eth3
were
> bonded (mode 1 ) after reboot the bond did not work. It came up OK but no
> data was passing through it. all other interfaces on the machine were
working.
>
> I decided to remove the bond, so after removing the bond i was left with
eth0
> using the same IP as the bond used. however it still does the same thing,
> it starts up with no errors but i cannot even ping the default gateway,
> tcpdump shows nothing on the interface.
>
> I have made sure of the following
> * no iptables installed
> * kernel modules for the NIC are loaded with no errors
> * the bond kernel module is not installed / all bond configs have been
removed
>
> Below is some info on the interface, it should be noted that all others are
OK
> the only 2 that were having the issue are eth0 and eth3 (the ex-bonded
ones)
>
> server1:/etc/sysconfig/network-scripts# ip route ?| grep 172.18
> 172.18.16.0/24 dev eth0 ?proto kernel ?scope link ?src 172.18.16.1
> default via 172.18.16.254 dev eth0
>
>
> # ifconfig eth0
> eth0 ? ? ?Link encap:Ethernet ?HWaddr 00:24:49:C8:66:98
> ? ? ? ? ?inet addr:172.18.16.1 ?Bcast:172.18.16.255 ?Mask:255.255.255.0
> ? ? ? ? ?UP BROADCAST RUNNING MULTICAST ?MTU:1500 ?Metric:1
> ? ? ? ? ?RX packets:0 errors:0 dropped:0 overruns:0 frame:0
> ? ? ? ? ?TX packets:7223 errors:0 dropped:0 overruns:0 carrier:0
> ? ? ? ? ?collisions:0 txqueuelen:1000
> ? ? ? ? ?RX bytes:0 (0.0 b) ?TX bytes:463918 (453.0 KiB)
> ? ? ? ? ?Interrupt:226 Memory:dc000000-dc012800
>
>
> If you look closely TX ?and RX are massively different, but I am not
> seeing anything on tcpdump even there is a large number of TX packets.
>
Just some more information on this issue.

I have tried different kernels and the same issue is still occurring.

# ethtool eth0
 Settings for eth0:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Supports auto-negotiation: Yes
	Advertised link modes:  10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Advertised auto-negotiation: Yes
	Speed: 1000Mb/s
	Duplex: Full
	Port: Twisted Pair
	PHYAD: 1
	Transceiver: internal
	Auto-negotiation: on
	Supports Wake-on: g
	Wake-on: d
	Link detected: yes

#mii-tool -v eth0
eth0: negotiated, link ok
  product info: vendor 00:08:18, model 54 rev 6
  basic mode:   autonegotiation enabled
  basic status: autonegotiation complete, link ok
  capabilities: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD
  advertising:  100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD flow-control


I am still racking my brains on what is causing this