Dump space

[Chris Burkart_1]

I have been reading posts all night and I'm still confuced on dump space. I have an R-390 with 3GB of ram. dmesg gives me the warning that the dump space is too small (only 1.5GB).
Primary swap is also dump. OK, so I make primary swap 3GB, but then I get a warning dump device can only be first 2GB of disk. Only 1 8GB disk in vg00. How will I ever be able to get a full dump if I'm limited to 2GB?

[T G Manikandan · Accepted solution]

It is not that on hp11.0 you require a dump space as ratio 1 to 1 as your physical memory as like 10.20 version.
It only uses portion of memory to the dump.

to find how much space you need for dump
you can use
#/sbin/crashconf -v

You are unable to extend the dump volume on your vg00 as it is a rule that the dump volume should be contigous on the disk.

If you need additional space to your dump you can configure a secondary swap device on the other disk.
You can set the priority of that to equal the priority of the primary swap so that both will be used during operations.
You can use SAM to configure the secondary swap device.

[Frank Slootweg]

As TG, implicitly, explains, you need another disk. If you only have one disk in vg00, then you can only have 2GB.

On the other hand, I would expect the PDC or/and IODC of a R390 to support 4GB dump per disk, instead of 2GB. See the "Dump Volume Warnings" in the "WARNINGS" section of the lvlnboot(1M) manual page. Perhaps a more hardware-knowledgable person can comment on that part.

In any case, make sure you are up to date on LVM-related patches. You don't mention your release, but as far as I know there have been patches for incorrect warnings from lvlnboot.