changing 4-node-cluster to 4 single-node clusters

[Heiko_1]

Hello,

We want to change a 4-node cluster into 4 single-node clusters. (Don't ask why, we just have to make it work ;-) )

The steps we have in mind are as follow:

1: remove node4 using sam
HAC->Cluster Admin.->Specif. Node Leave CL.
2: edit cmclconf.ascii on node4 removing al
references to node1-3
3: do a cmcheckconf -C cmclconf.ascii -p pack4.ascii

4: cmapllyconf -C cmclconf.ascii -p pack4.ascii

this all looks to simple for me.
Is there anything i overlooked or some thing i need to checkfirst.

Hope someone can help me out,

with kind regards,

Heiko

[John Palmer]

If the clusters are on the same network, you'll also have to give each one a different cluster name.

What I'd do for each node is:

1. cmmodpkg to ensure packages can't switch.
2. cmhaltnode
3. cmdeleteconf
4. Reconfigure as a single node cluster with a unique name.
5. Start single node cluster.

Regards,
John

[Heiko_1]

John,

is it possible to test this procedure on one of the nodes of the cluster without effecting the other 3?

Then there is the issue of Reconfiguring as a single node ( with a unique name ) cluster. Can that be done with editing the cmclconf.ascii, as i mentioned in my original posting ?.
I'm totally new at this Service Guard software. So my questions may seem a little stupid.

[melvyn burnard]

Hmm, interesting step forwards?

Anyway, there are a few things you will need to do.
Halt the cluster.
vgchange -c n for each shared VG to remove the existing cluster ID.
On each node you will need a cluster ascii file. You can either use cmquerycl -v -C asciifilename -n nodename on each node, or you could copy your existing ascii file to each node and then edit that.
Whichever way, you will need to edit the scii file to create a new unique cluster name for each cluster, ensure you ONLY have entries for the single node,
Ensure you have the CORRECT VG 's specified (to confirm these are to be used in each cluster.) I would also suggest you vgexport any VG on a node that will NOT be used on thaht node.
You would then have to change the package config file(s) on the node to ensure you only have that single node specified.

Next step is to vgchange -a y any vgs that will be used by packages on the node, and then use cmapplyconf -v -C asciifile -P packageconffile to apply the cluster binary.

cmruncl

HT

[Ashwani Kashyap]

Hi, you would be better off removing one node at a time from the cluster . Here is what I think the steps should .

On node 4 , halt the packages owned by node 4 and failover any other packages that node 4 is adoptive node for .

Remove node4 from the cluster using cmhaltnode.

Edit the cluster ascii file . Change the cluster name , remove any references of other nodes and networks on other nodes , remove VG not belonging to node 4 .

Edit package conf file , remove all adoptive node names , check the subnet .

Do a vgchange -c n on all the VGs owned by node4 . Export out all other VG's previously referenced . do a vgchange -a y and then deactivate them again .

Apply the conf using cmapplyconf and recreate the binaries .

Check your package hatl/run scripts and any other monitoring scripts you use to reflect the changes .

Startup the new cluster now .

If it works do the same on each node .

[Sanjay_6]

Hi Heiko,

you can remove one single node from a running cluster. Build a seperate single node cluster using that node and try.

Try this link below for more help,

http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/B3936-90053/B3936-90053_top.html&con=/hpux/onlinedocs/B3936-90053/00/00/48-con.html&toc=/hpux/onlinedocs/B3936-90053/00/00/48-toc.html&searchterms=remove%20node&queryid=20020925-121859

Hope this helps.

Regds

[Heiko_1]

Thnx to all for the replies.

Now we were confident enough to test it on a running cluster and we were able to extract one node from te cluster without problems.

again thnx

Heiko