Wednesday 19 March 2014

SEA AIX stops working, recreating SEA without hating AIX

Hm... where to start?
Well, we do have IBM pSeries p570. Actually, we have two racks of it. We are using IBM LPAR virtualization. We have 4 LPAR per rack with two(for redundancy (for what else))) VIOS server per rack for virtualization of CPU and RAM.
Are IBM support introduce as with concept of Shared Ethernet Adapter(SEA) when they need to implement SEA for enabling separate 10Gb/s ethernet interface for backing up are servers that was running on LPAR.

I hope that you do understand concept of SEA. Point of SEA is that you have shared ethernet interface that you can share thought VIOS among all LPAR that are connected to that VIOS.

If you are Linux admin (like  I am) then you will probably  need some time (like I did) to understand why IBM make concept of  SEA so complicated and creating of it hard as living hell. Believe me, reading IBM redbook is one thing and actually creating SEA is totally different thing(at least it was or me).

Ok, here are things that you need to know before you start to create SEA. Once you create SEA it will work perfectly as long as no network issues with physical interface occurred.

Things that you need for SEA:
1. At least one physical ethernet interface connected to your network equipment. You network will route traffic from that interface to your desired destination.
2.One virtual ethernet interface that will be in VLAN 1 for communicating between LPAR
3.Optional: One virtual ethernet interface that will be in VLAN 99 for control channel between two VIOS. This is for case that you want to have redundant SEA between VIOS'es.

VERY IMPORTANT: SEA IS CREATED ON VIOS AND YOU DO NOT ASSING IP ADDRESS TO IT.

I will show you simplest possible case of creating SEA.

$ lsdev |grep ent
ent0             Available   10 Gigabit Ethernet-SR PCI-X 2.0 DDR Adapter (1410eb02)
ent1             Available   10 Gigabit Ethernet-SR PCI-X 2.0 DDR Adapter (1410eb02)
ent2             Available   Logical Host Ethernet Port (lp-hea)
ent3             Available   Virtual I/O Ethernet Adapter (l-lan)
ent4             Available   Virtual I/O Ethernet Adapter (l-lan)

$ mkvdev -sea ent1 -vadapter ent4 -default ent4 -defaultid 1
ent5 Available
$ lsdev |grep ent
ent0             Available   10 Gigabit Ethernet-SR PCI-X 2.0 DDR Adapter (1410eb02)
ent1             Available   10 Gigabit Ethernet-SR PCI-X 2.0 DDR Adapter (1410eb02)
ent2             Available   Logical Host Ethernet Port (lp-hea)
ent3             Available   Virtual I/O Ethernet Adapter (l-lan)
ent4             Available   Virtual I/O Ethernet Adapter (l-lan)
ent5             Available   Shared Ethernet Adapter



Suppose ent1 is physical ethernet interface. Check with your network admin if he can see state on that interface. State should be UP. If it is not UP, he should do UP/DOWN of that port on network equipment until he can see that port state is UP.  If he can not see this interface correctly, you could not make SEA to work correctly.
ent4 is out virtual ethernet interface and it is in VLAN 1 and should have access to external network.

Chance that you create SEA with no trouble is almost  zero so you need to be very patient.

In case that you have any trouble in configuring SEA, maybe best thing to do is that you remove all virtual interface that you need to work with. In are case that is ent4 and ent5.

You could also create link aggregated interface from ent1 and ent2. In this case you will have redundancy on physical interfaces,too.





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