There is the production network where there are switches that connect all the servers, but I would sometimes want to connect the two database servers to each other using one single line, since there are spare network adapters plus this seems to improve statability.

I mean, I have a network like 172.10.x.x where all machines are in, now I'm setting both spare adapters which was connected directly to use the 10.10.10.x network, and I want them to accomplish all sync stuff through this.

in the past two days I've spent some time doing this, like what I'm listing below

HADR_LOCAL_HOST
HADR_REMOTE_HOST
HADR_LOCAL_SVC
HADR_REMOTE_SVC
HADR_REMOTE_INST

on both servers I've set them right, while for the alternate server address which was supposed to help client reroute I've specified the 172 network.

I have successfully started hadr on database XX as standby, then started hadr on database XX as primary on the other server, get snapshot for db on XX answers the right way, one standby and primary for the other, nearsync and connected

Okay...the problem why I'm saying a whole bunch of this is, while I input 'takeover hadr on database netdb' on the standby, I failed, no SQLXXXXX number to indicate anything and reason code has nothing between the double quotes.

After this insuccessful takeover, the original primary has changed itself into a standby but vise not versa, the standby stays standby.

So I'm wondering if what I have wanted, the separated network for sync and the usual query, is possible.

I did searched the forum and I hope this is not a well-known everybody-solve-it-on-their-own question...

I'm using DB2 9.5, thank you for your help.

You can certainly specify an alternate network (other than to be used by applications connecting to the database) for the primary and standby to talk to each other as defined in the HADR config. I do this whenever possible, usually making it a private network, and sometimes just using a crossover cable (no switch or router) if the machines are close enough together.

As to why it is not working, I don't know. Make sure each database has its own HADR ports (Service), and that the port numbers are opposite on the primary and standby.

Maybe you need to post your HADR setup in the db cfg.

Marcus, thank you so much, I'm going to figure out today where I was wrong.

I am using a crossover cable, I just didn't know what that was called yesterday.

In the "old days", a special cable was required with the wires in reverse order (crossed-over) on each end (if not going through a router/switch/hub). Most new network adapters can automatically detect a direct connection to another computer and can electronically switch the wires as needed.

ok I've done it...now the takeover works.

I don't quite know how things worked out. just a fresh new backup and new restore, and it started to work all right.....