HDR over secondary network

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MMarks - 22 Dec 2005 18:42 GMT

HPUX machines, Informix 9.4

We have a primary database server, srvA, and a server we want to use
HDR to back the database up to, srvB.

Both machines are on our primary network, as well as a sync network,
where they have a different set of IP addresses (which are identified
in the hosts files as srvA-sync and srvB-sync).
We would like to do the HDR over the sync network.

If I set the sqlhosts files to do HDR over the primary network, it
works fine.
If I set the sqlhosts files to do HDR over the sync network, it only
works if srvB is not attached to the primary network.

if srvB is attached to the sync network, I get the errors:
11:53:26 DR: new type = primary, secondary server name = srvB-db
11:53:26 DR: Cannot connect to secondary server
11:53:26 DR: Turned off on primary server

11:53:35 DR: Trying to connect to primary server = srvA-db
11:53:35 DR: Cannot connect to primary server
11:53:35 DR: Turned off on secondary server

What is the trick to getting HDR to work over the secondary network?

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Art S. Kagel - 22 Dec 2005 19:43 GMT

> HPUX machines, Informix 9.4
>
[quoted text clipped - 21 lines]
>
> What is the trick to getting HDR to work over the secondary network?

Just to get the obvious out of the way ... is there a route defined between
the two networks?

Art S. Kagel

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MMarks - 22 Dec 2005 20:29 GMT

>Just to get the obvious out of the way ... is there a route defined between
>the two networks?

Yes, but I don't know if it's relevant. We want the HDR to function
entirely over the secondary network just as it does when the primary
network does not exist.

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Art S. Kagel - 22 Dec 2005 22:55 GMT

>>Just to get the obvious out of the way ... is there a route defined between
>>the two networks?
>
> Yes, but I don't know if it's relevant. We want the HDR to function
> entirely over the secondary network just as it does when the primary
> network does not exist.

OK, post the sqlhosts entries for the two servers and the exact onmode
command you are trying to use to initiate HDR.

Art S. Kagel

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scottishpoet - 23 Dec 2005 14:14 GMT

server name = srvB-db

but you want srvB-sync

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MMarks - 23 Dec 2005 16:14 GMT

>OK, post the sqlhosts entries for the two servers and the exact onmode
>command you are trying to use to initiate HDR.

on srvA:

srvA    onipcshm    srvA    srvA
srvB    onsoctcp    srvB-sync    istarcars

(istarcars is the name of the service we use for remote DB
connections)

command: onmode -d primary srvB

on srvB

srvB     onipcshm    srvB    srvB
srvA    onsoctcp    srvA-sync    istarcars

command: onmode -d secondary srvA

This works fine if srvB only has a network connection to the sync
network.
If srvA has NIC cards on both sync and the standard network, I have to
change the "srv?-sync" parts of the sql hosts file to the standard
name, then it will work over the standard network only.

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ajaykg68@gmail.com - 26 Dec 2005 16:38 GMT

Verify if you have trusted informix account on two machines when sync
network is use.

If you see the following message in online.log of paried server, the
two machines does not have tursted informix account:

08:30:18 listener-thread: err = -956: oserr = 0: errstr =
srvA-sync.com: Client host or user informix@srvA-sync.com is not
trusted by the server.

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Andreas Legner - 27 Dec 2005 22:15 GMT

Hmmm ... if two networks are used, srvB and srvB-sync would resolve to different ip addresses,
similar would be true for srvA and srvA-sync, wouldn't it?

So is srvA (DBSERVER...) listening on srvA or on srvA-sync now?

In other words: the two sqlhosts files' informations don't seem to match.

HTH,
Andreas

>>OK, post the sqlhosts entries for the two servers and the exact onmode
>>command you are trying to use to initiate HDR.
[quoted text clipped - 21 lines]
> change the "srv?-sync" parts of the sql hosts file to the standard
> name, then it will work over the standard network only.

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MMarks - 30 Dec 2005 04:21 GMT

> Hmmm ... if two networks are used, srvB and srvB-sync would resolve to different ip addresses,
> similar would be true for srvA and srvA-sync, wouldn't it?

Correct.

The machines are on two networks. as srvA and srvB they have IP
addresses such as X.X.25.X. as srvA-sync and srvB-sync, they have IP
addresses such as X.X.27.X

srvA is always connected to both networks.

the replication over the X.X.27.X network only works if srvB has no
connection to the X.X.25.X network.

In this case, I can set each machine to have an SQL hosts line such as:
srvA onsoctcp srvA-sync istarcars
to identify the other machine, then use
onmode -d primary srvB
and
onmode -d secondary srvA

This works fine and replicates over the X.X.27.X network. (using
srvB-sync and srvA-sync does not work).

If srvB has connections to both networks, changing the references to
srvA-sync or srvB-sync in sqlhosts to just plain srvA or srvB allows
connections over the X.X.25.X network, but I cannot find a way to get
the connections over the X.X.27.X network.

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Art S. Kagel - 27 Dec 2005 23:05 GMT

>>OK, post the sqlhosts entries for the two servers and the exact onmode
>>command you are trying to use to initiate HDR.
[quoted text clipped - 15 lines]
>
> command: onmode -d secondary srvA

You cannot use srvA here or srvB in the onmode above because srvA & srvB are
shared memory connectsion which cannot be used to communicate between
different machines nor between multiple instances on the same machine. You
MUST use a tcp/ip or other supported network connection alias.

Art S. Kagel

> This works fine if srvB only has a network connection to the sync
> network.
> If srvA has NIC cards on both sync and the standard network, I have to
> change the "srv?-sync" parts of the sql hosts file to the standard
> name, then it will work over the standard network only.

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