AIX

thanks a lot bakunin

OK, this virtual NICs in each LPAR are independant theyselft, the etherchannel is at the VIO level, and this etherchannel allows several VLANs

yes #8 is from a Production server
got you point about the subnet mask (the IPs are not real) anyway even when they are not real my network team uses IP 10.4.25 - using always /24 as a mask

talking about gateway I don't remember If I mentioned it, en1 takes the same gateway set in en0

I have no idea, that is by default I don't think our customer added that

hmm, in 3 you said there is no VIOS, now i am confused. Please describe your (physical and virtual) network setup in detail, from the switch to the kernel.

I don't think this is default. I even suppose this is why you lose connectivity sometimes. If a packet comes in on interface 1 this doesn't necessarily have to answer if two (or more) interfaces are in the same subnet. It could be any other interface in this network too. If your en1 answers and this traffic is routed to the loopback device, the connection would never come to pass.

I suggest you investigate this, IMHO this is the most likely source of the problem.

For a proper routing table you need 3 entries:

1) a default route, telling the system where to send everything for which no rule exists,

2) route directing everything on the "home net" to the interface in the net,

3) a loopback, directing 127/8 to lo0.

For instance: your network on en0 is 10.10.10/24, your IP is 11. Your second network is "10.10.20/24", IP is 11 again. You will need 4 rules for that:


1) default -> nearest router, say, 10.10.10.1
2) 10.10.10/24 -> 10.10.10.11
3) 10.10.20/24 -> 10.10.20.11
4) 127/8 -> 127.0.0.1

I hope this helps.

OK,

AIX-TSM Server is a Power 710, where AIX was installed on top of it. This servers has no VIO.

has two NICs
en0 administration
en1-en2 backup in etherchannel ( anyway without etherchannel we tried as well and the issue is still there just using en1)

Good point

we might need to take a look at this then