Veritas Cluster Server

[Mohammad Adnan]

We are planning to run VCS 3.5 on two HP 9000/K460. The server is running LVM now.
Do we have to have Veritas FS and VM in order to get the cluster going?
I am very new to HP-UX so pardon my ignorance.
Thanks.

Regards,
Mohammad

[Ross Zubritski]

Just a quick question. Why run VCS vs. Service Guard.

Regards,

RZ

[Mohammad Adnan]

It's a mixed environment with AIX, Solaris, HP and NT. For HA solution, management wants a standard software and VCS seems to handle most platforms. HP is the smallest part of this infrastructure, actually just this one system.

Thanks.
Mohammad

[Michael Steele_2]

In general there are three phases to plan for in a cluster environment, HW fault tolerance, LVM or VXVM and the SG binaries.

If you've already got a SG cluster running then phase one is completed, if not, you can't ignore it and several fail over tests will have to planned for. For example, pulling the primary LAN, TOC'ing either nodes, accounting for the cluster lock disk, disk arrays are usually used instead of JBODS, etc.

Phase two is going to have to be an LVM to VXVM migration unless you're starting from scratch. You say you've already got two K460's so I don't know for sure since you haven???t' elaborated. But here is a migration link for LVM to VXVM anyway:

http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/B3936-90053/B3936-90053_top.html&con=/hpux/onlinedocs/B3936-90053/00/00/85-con.html&toc=/hpux/onlinedocs/B3936-90053/00/00/85-toc.html&searchterms=vxvm%7cmigration%7clvm&queryid=20030331-183302

For CVM to work you'll need a mirror root volume and this means advanced vxvm and not the base product. Like online JFS it'll cost more because this is what Veritas does. But you're in a PA-RISC based system and you'll have to distinguish this from the Itanium versions since there's an extra boot up binary called EIF in the Itanium version and you don't want this. So be aware of the PA-RISC distinction.

Remember this VXVM layer:

disk => plex => volume

Online JFS, Base JFS and HFS are still be around but get online JFS for the obvious reasons needed in the high availability environment that you're planning. High availability is what LVM and CVM are all about.

Note that you can also use a software enabled RAID 5 through vxvm and that Service Guard will also work with VXVM if you want it to, but I've heard it has limitations. However, since you're PA-RISC you might be better off with VXVM and SG instead of VXVM and CVM.

And here's a nice link on CVM:

http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/B3936-90065/B3936-90065_top.html&con=/hpux/onlinedocs/B3936-90065/00/00/39-con.html&toc=/hpux/onlinedocs/B3936-90065/00/00/39-toc.html&searchterms=cvm&queryid=20030331-185920

Failover clusters are worthy adversaries so take some classes, and with your PA-RISC based architecture you may be building a peculiar beast that not many other people will have.

[Mohammad Adnan]

Thank you very much for a detailed response.
It will help me present few more options to the management.
I was browsing the veritas website and I found that VCS 3.5 for HP-UX includes LVM support as a bundled agent. Since LVM is already running on the K460 we have, I think we will stay with it and purchase VCS as an HA software.

Regards,
Mohammad