2 BM Servers Natting to Same Internal Address

Question

Can this be done? I'm changing my BM server that does natting, to a different server on a different external subnet. To test it's functionality, without downing the old server, I've set natting up the same on the new as the old. This means that during the testing phase, I've got 2 different external addresses natted to the same internal address. I've been having some erratic problems with this. Could it be that this is causing a conflict?

Answer 1

What you can do is to set up a second BM server in parallel to the
first one, (and eventually perhaps cluster the two) for testing.
Make all addresses you point to secondary addresses (except VPN) on the
old server. This means the internal proxy address needs to be a
secondary address, which can be done by readdressing the private side
of the BM server and adding the old address back as a secondary.
Once the proxy address is a secondary, it becomes much more portable.
You would have one or two NCF files to add the secondary addresses as
needed. (Do not add them in inetcfg). And another NCF to delete the
secondaries.
Unload proxy on the old server, then load it on the new one (once it
has been configured with old server addresses). Unload secondaries on
old server (with NCF) and add to new one (with NCF file) - NAT's and
filtering need to be set up in advance. All your traffic will move to
the new server as long as you avoided address duplication. You test
and see how things work.
Reverse the process to go back to the old server.
This is what I call a 'poor man's cluster', as you are doing manually
what simple cluster scripts would do (unload proxy, add addresses...)
Process is documented in my BMgr book - see URL below.
Craig Johnson
Novell Knowledge Partner
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