VMS DIsk shadowing - SYSTEM-F-INCSHAMEM

[techsay]

Hi All,

I have a DEC Alpha 1000A running OpenVMS 7.3 with disk shadowing of the sytem disk. The system disk is DSA0: with the following members $1$dkb0: and $1$dkb100: (all on the same controller). Both disks are DEC RZ1BB-CS. I started getting errors on $1$dkb100: the other day and thought I should replace the disk with another RZ1BB-CS disk. So, I did the following:

1.) Dismount $1$dkb100:
2.) Replaced $1$dkb100: with spare RZ1BB-CS drive
3.) issued mount/system/confirm dsa0:/shadow=($1$dkb0:, $1$dkb100 SYSTEM

I get the following error:
-SYSTEM-F-INCSHAMEM, incompatiable shadow set member.

I then initialized the new RZ1BB-CS disk. mounted it and copied files to it just to make sure it was operational. It was. I then dismounted and removed that disk.

I then placed the old disk back in and issued the above commands and all went ok. But I am stuck with the drive that was throwing errors. I then tried to replace $1$dkb0: after the orignal shadow set completed its merge. I get the same error.

The only difference that I see is in during the mounting phase where shadowing tells you that it is bringing in a new member I see a difference in the Owner UIC. For example:

The orginal disk when placed into the shadow set says its owner is [1,1]. The new disk says its owner is COMVAX. COMVAX UIC is [1,5]. The previous administrator of this system was let go and the Account name he gave me has full priviledges and is the UIC of [1,5].

I have changed out shadow set members on other systems with now problem like this. I not sure what else to check. Can RZ1BB-CS drives have different gemotries?

Can anyone help.

 

[js2801]

It been a long time since I've dealt with VMS, and especially shadow sets, so I'm guessing a bit. However I think you have to dismount DKB100 and remove it from the shadow set. I believe there is a qualifier on the dismount command to do that. Then you may add the new disk to the shadow set. See help dismount and help mount.

Good luck

 

[HughSamson]

Don't know if this helps, but HP website's doco indicates the following re geometry in relation to the error you are receiving... maybe do a basic check on the size that's showing for each of the units and see if the controllers are reporting differing sizes..??

"If you are running the current shadowing ECOs or the shadowing foundin recent OpenVMS releases, the shadowset member geometry is not a factor -- the total number of blocks present on each device must match, but there are no longer any geometry-specific restrictions with volume
shadowing.

There is no particular supported means to shadow devices with differing numbers of blocks, but sometimes disks or controllers can have the number of available blocks altered through some controller- or hardware-specific means. The other obvious approach involves the use of a consistent set of disk devices as all members of a shadowset.