Virtual IP Address

[MoreFeo]

Hi, we're trying to make a virtual IP address network interface, and we're having some trouble.

In a server with 2 physical adapters making an etherchannel and only one IP address it is working fine, but in servers with 2 physical adapters, each with its own IP address it's creating the virtual adapter but it cannot be reached from outside the server.

In the first server, the etherchannel has its IP address in the same subnet than the virtual adapter (10.1.10.X).

In the other servers, adapter en0 has an IP in a subnet (10.1.10.X) and en1 has its IP in another subnet (10.1.7.X)
The IP address of the virtual adapter is in the same subnet as en0 (10.1.10.X)

We've tried creating the virtual adapter in several ways, with the same results:

mkdev -c if -s VI -t vi -a netaddr=10.1.10.xxx -a netmask=255.255.255.0 -a state=up (also tried with -a interface_names=en0)

and

ifconfig vi0 10.1.10.xxx netmask 0xffffff00 broadcast 10.1.10.255

Any ideas?

 

[khalidaaa]

If i do understood your question, have a look to this:

The adapters that you plan to use for your EtherChannel must not have an IP address configured on them before you start this procedure. When configuring an EtherChannel with adapters that were previously configured with an IP address, make sure that their interfaces are in the detach state. The adapters to be added to the EtherChannel cannot have interfaces configured in the up state in the Object Data Manager (ODM), which will happen if their IP addresses were configured using SMIT. This may cause problems bringing up the EtherChannel when the machine is rebooted because the underlying interface is configured before the EtherChannel with the information found in ODM. Therefore, when the EtherChannel is configured, it finds that one of its adapters is already being used. To change this, before creating the EtherChannel, type smitty chinet, select each of the interfaces of the adapters to be included in the EtherChannel, and change its state value to detach. This will ensure that when the machine is rebooted the EtherChannel can be configured without errors.

http://publib.boulder.ibm.com/infoc...mn/doc/commadmndita/etherchannel_consider.htm

Regards,
Khalid

 

[khalidaaa]

Usually you have to assign the IP address on the newly created ent after creating the etherchannel not on the physical adapters!

Configure IP over the newly-created EtherChannel device by typing smitty chinet at the command line.

http://publib.boulder.ibm.com/infoc...mn/doc/commadmndita/etherchannel_consider.htm

Regards,
Khalid

 

[MoreFeo]

No, it's not exactly what I'm looking for.
The etherchannel is already created, and it's working fine.

What is not working is a virtual adapter we need to create.

What we've got (and working):
A server1 with 2 physical adapters, with etherchannel ALREADY created and working (en2), with IP in subnet A.

A server2 with 2 physical adapters, each adapter with its own IP, en0 in subnet A, en1 in subnet B.

What we need:
Add on each server a virtual adapter to assign these servers an aditional IP address in subnet A.

What works fine:
Adding the virtual adapter in server1 is working fine, we can reach the server thru this new address.

What is not working:
Addind the virtual adapter in server is not working. It adds the adapter, but we cannot reach the server thru this new address.

 

[p5wizard]

A possible workaround: how about creating an IP alias on the physical ethernet interface (no need for the vi0 interface)

ifconfig en0 alias 10.1.10.xxx netmask 255.255.255.0

HTH,

p5wizard

 

[MoreFeo]

I'll try with the alias and see if it can fit our needs. We are trying to make some kind of home-made HACMP, that will bring up the extra IP address in another node in case it fails in the first one, this is why we were thinking about virtual adapters, because they're not bound to any adapter. But I see that in our configuration aliases can give us what we need.

Thanks