AIX network interface state question


I have a network  en0 card and state shows as Stopped, but IPs are active on the interface.  Can you  please  tell me why it went to stopped state?
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Zephyr ICTCloud ArchitectCommented:
Can you post the results of netstat -i  ?

Are you sure that the physical card is still active? Probably called ent0 ...
I assume when saying "shows as Stopped" you mean the "status" information as displayed by "lsdev", right?

This status is normally shown when the interface has been marked "down" by means of the chdev command using its -P flag and a reboot hasn't been performed yet.

What do you see with "ifconfig en0" and "lsattr -El en0"?
mokkanAuthor Commented:
Yes, here is the output.

# lsdev   |  grep  -i  network
en0             Stopped         Standard Ethernet Network Interface
en1             Defined         Standard Ethernet Network Interface
en2             Defined         Standard Ethernet Network Interface

# lsattr  -El  en0
alias4, IPv4 Alias including Subnet Mask              True
alias4, IPv4 Alias including Subnet Mask              True
alias6                                   IPv6 Alias including Prefix Length            True
arp           on                         Address Resolution Protocol (ARP)             True
authority                                Authorized Users                              True
broadcast                                Broadcast Address                             True
monitor       off                        Enable/Disable monitor attribute              True
mtu           1500                       Maximum IP Packet Size for This Device        True
mtu_bypass    off                        Enable/Disable largesend for virtual Ethernet True
netaddr               Internet Address                              True
netaddr6                                 IPv6 Internet Address                         True
netmask              Subnet Mask                                   True
prefixlen                                Prefix Length for IPv6 Internet Address       True
remmtu        576                        Maximum IP Packet Size for REMOTE Networks    True
rfc1323                                  Enable/Disable TCP RFC 1323 Window Scaling    True
security      none                       Security Level                                True
state         down                       Current Interface Status                      True
tcp_mssdflt                              Set TCP Maximum Segment Size                  True
tcp_nodelay                              Enable/Disable TCP_NODELAY Option             True
tcp_recvspace                            Set Socket Buffer Space for Receiving         True
tcp_sendspace                            Set Socket Buffer Space for Sending           True
thread        off                        Enable/Disable thread attribute               True
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The "lsattr" command shows "state" as "down" and that's the reason for the "Stopped" status shown by "lsdev".

What does "ifconfig en0" say?

Should it still show "up" then the interface must indeed have  been marked "down" by means of the
chdev command with "-P".

If you see "down" with "ifconfig" then the interface has been marked down by means of the "ifconfig" command.
In such a case the system will no longer transmit messages through that interface. Often, but not always (!) the interface is reset to disable reception of messages.
Routes using the interface are not reset either, so it can well be that your en0 can still receive messages and can even send ICMP replies.

After the next reboot the interface will neither send nor receive anything, unless you set it "up" again, best by means of "smitty chinet".
mokkanAuthor Commented:
Thank  you very much. Ifconfig output shows as UP and IPs are pingable.

I found IP conflict message in errpt.  If  the IP addresses is conflict with another server. Would AIX make inferace state to be down?
AIX would try to mark the interface as DOWN in "ifconfig". So if it's still UP there then I doubt that the address coflict really affects that interface.

Is this a cluster system?
mokkanAuthor Commented:
Yes,  we are running  VCS cluster top of it,   some how the IP is configured in alias as well as mnaged by VCS, that was the problem for confilict, but not sure that would make eno state to down ? Is it possible ?
Could it be that the IP address is flipping back and forth between the nodes? In such cases the final results might be unpredictable.

Are the "lsattr" state as well as the "lsdev" status still the same as before? Or do the states change?

I don't know VCS very well - could it be that the cluster manager handles its interfaces on its own, bypassing the ODM? If so then what you see could be quite normal!

And if VCS doesn't know anything about defined IP aliases (who defined them then?) there might well arise an address conflict in case of node failover.

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mokkanAuthor Commented:
thank  you very much
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