HP LAN Interfaces Problem

[David_492]

Dear all

I have one HP UNIX Server partioned into two nodes node1 and node2 (npar) hardware partion each node has it's own LAN Primary interface and it's own LAN Stand by interface. i configured the ip address as bellow
node1
Primary Interface IP : 10.0.1.1
Stand By Interface IP : 10.0.1.90

node2
Primary Interface IP : 10.0.1.2
Stand By Interface IP :10.0.1.80
AND AS WE SEE all the ip address's are on the same network and subnet.
Now when i enable the interface of the standby either on the node1 or node2 interface i lost the whole connection to the server
i connect back by disable the standby interface
My question why is this happining?
and how i can make LAN Redundancy between the Primary interface and Standby Interface incase of failover of the Primary interface on any of these two partioned nodes?

Any suggestions

Thank you all i apprcaiate it




Any suggestions
Thank you all

[Patrick Wallek]

Having 2 interfaces on the same subnet is not really supported by HP. You can have redundency between the cards on each machine by utilizing HP's Auto Port Aggregation (APA) software or MC/Service Guard software.

[Jeff Schussele]

David,

What are you using SW-wise to perform the NIC failover - Service Guard or APA?

In the case of MC/SG the standby should NOT be assigned an IP. One lets MC/SG do the work. So down the standby card & unplumb it.

I'm not sure about APA - we don't use it.

Jeff

[David_492]

M/C Service Gaurd

[Patrick Wallek]

Follow Jeff's instructions. You will also need to configure the standby card in the cluster configuration file. MC/SG will automatically re-assign the IP address to the standy card in case the primary fails.

[James Randall]

Jeff is right about MC/SG.

APA....you basically gang two interfaces into one LOGICAL Interface....and assign the LOGICAL Interface the IP address.

Therefore you get twice the bandwidth normally....and if either leg goes down...You are still on the LAN.

Cheers.

James

[rick jones]

when you ifconfig two phsyical (in the eyes of the transport) nics into the same IP subnet, traffic will be received on both, but will only go-out one of the interfaces. if both interfaces do not have equal connectivity, this can result in a loss of connectivity to the system.

as pointed-out, APA is perhaps the best way to implement link-level HA.

if you do not want to go the APA route, then you need to:

*) make sure that both NICs do indeed have the same connectivity to the rest of the net (from your description of what happened, they might not)

and

*) only one of them is actually "up" at a time.

Now, if one does want both NICs configured at the same time, there can be some help in setting ip_strong_es_model to one - at that point source IP address is included in outbound route lookup and so traffic that comes-in on an interface will tend to go back out that same interface.

ftp://ftp.cup.hp.com/dist/networking/briefs/annotated_ndd.txt

[David_492]

Dear all

i use MC/SG and i do not assign any ip address to the standby interface as Mr.Jeff Said and make the test incase the primary interface failed but it doesnot switch to the standby LAN why?

Any suggestions

Thank you all