topic Re: shadowing the system disk problems in Operating System - OpenVMS

shadowing the system disk problems

Donald Schleicher — Thu, 03 Jun 2004 07:23:15 GMT

Re: shadowing the system disk problems

Donald Schleicher — Thu, 03 Jun 2004 07:31:23 GMT

Sorry about that. Anyway, the problem I'm having is that I don't understand how to shadow the system disk on a new ES47 server with OpenVMS 7.3-2.

I inited the system disk and installed OpenVMS on disk $4$dkb0. I set the shadowing parameter to "2" and set the allocation class to "4" and added these to the modparams.dat file. I have two identical disks, $4$dkb0: and $4$dkb100:, that I'm trying to make a shadow set out of with the command "mount/system dsa0: /shadow=($4$dkb0:,$4$dkb100) system".

I can get this to work when I boot off the CD and the dkb0: disk is not mounted. However, when I boot off the system disk, its mounted, and the above command won't work because the dkb0 disk is mounted already.

Can anyone tell me what I'm missing? Do I need to start over and init the two disks together with "init/shadow"? I've set up non-system shadow sets before, but this is the first install I've done from scratch.

thanks,
don

Re: shadowing the system disk problems

Wim Van den Wyngaert — Thu, 03 Jun 2004 07:43:53 GMT

When you boot you don't have to mount the system disk shadow set. It will use the last version (1 or both of the disks) it has seen.
Otherwise, add the 2nd disk to the shadow set and reboot.

Just hope you set shadow_sys_disk to 1 too.

Re: shadowing the system disk problems

Willem Grooters — Thu, 03 Jun 2004 07:49:29 GMT

Quick shot.
IIRC, there are a number of sysgen parameters to be set

SHADOW_SYS_DISK to indicate that the system disk is a shadowset this must be '1' (I presume)
SHADOW_SYS_TMO (is set to 120 seconds)
SHADOW_SYS_UNIT (Unit number, DSAnnnn, 0-9999): the system disk set
SHADOW_SYS_WAIT (is set to 480 seconds)

If you have another system available, check these parameters on that one.

There might be more to do but this is from 'fast memory'.

Willem

Re: shadowing the system disk problems

Jan van den Ende — Thu, 03 Jun 2004 08:06:48 GMT

Donald,

Wim & Willem both are close, but not complete.

SYSGEN param SHADOWING should be set to 2 to enable shadowing (to load the shadowdriver very early)
( 2 = Host based Shadowing; 1 = the now obsolete Controler based shadowing )

SYSGEN param SHADOW_SYS_DISK set to 1
(meaning, use shadowdriver for system disk mounting)

SYSGEN param SHADOW_SYS_UNIT to define the number of the shadowset unit ( DSA# ).

SHADOW_SYS_WAIT seconds available for shadow set and all members of other clusternodes to become configured, before error action is taken

If you have a SAN configuration, and especially if that is multi-site, you really MUST acquire the Volume Shadowing Manual, because then a lot of other things come in play as well.

Jan

Re: shadowing the system disk problems

Donald Schleicher — Thu, 03 Jun 2004 10:45:03 GMT

All right... The system disk is now shadowed. The params for shadowing, shadow_sys_disk, shadow_sys_unit, and alloclass have been set and added to my modparams file.

Thanks for the help...

don

Re: shadowing the system disk problems

Jan van den Ende — Thu, 03 Jun 2004 12:56:54 GMT

Don,

Glad to be of help (like the lot that hang around here all are)

I just noticed you are new here, so

WELCOME.

Since you are new, may I direct you to the 'forum etiquette'?

Please have a look at

http://forums1.itrc.hp.com/service/forums/helptips.do

Enjoy VMS,
enjoy this forum!

Jan