crash dump config

[PVR]

Hi !

I got a 11.31 box. Size of my dump device is 5GB(Its not the same swap) I want to extend it to 8GB. I removed the dump using;
lvrmboot -d dump /dev/vg00
Then created it with large size
lvcreate -C y -r n -n dump /dev/vg00
Then added into the configuration;
lvlnboot -d dump /dev/vg00

Do I need to do any extra configuration ? Will the system use the total 8Gb for dumping now on ?

Thanks much in advance..

[Prashanth Waugh]

Hi PVR,

As per my knowledge, the steps which you have mention are correct and no need extra to do extra configeratin

Regards
Prashant

[Avinash20]

Hmm. I would suggest the below.

Please refer to

http://docs.hp.com/en/5992-4589/ch03s07.html

[Avinash20]

Also you are saying that you like to extend it ??

Then where from lvcreate comes ? its shud be lvextend and also it will be contiguous by default
If you are creating a new dump, please refer to the above url

[Avinash20]

Also for dump, I would advice you to set a contiguous allocation policy using the -C y option and disable bad block relocation using the -r n option.

[skt_skt]

here is how i confifugure the existing swap device as dump

There is always a need of configuring the swap device as a dump device too to get collect a full crash dump incase a system crash.

Here are the steps


â ¢ Create a Logical Volume with strict, contiguous and bad block relocation set to OFF
# lvchange -C y -s y -r n /dev/vgswap/lvol1

â ¢ Add the new dump LV in /etc/fstab as shown below:
/dev/vgswap/lvol1 ... dump defaults 0 0

â ¢ Edit /etc/rc.config.d/crashconf as below: Most of the cases they are set by default.
CRASHCONF_ENABLED=1
CRASHCONF_READ_FSTAB=1
CRASHCONF_REPLACE=0

â ¢ Issue "/sbin/rc1.d/S080crashconf start" to update the dump devices, it
should return EXIT CODE: 0 for a successful operation.

â ¢ To verify your dump configuration issue "crashconf" and you should
see something like the example below:

[/root] crashconf
Crash dump configuration has been changed since boot.

CLASS PAGES INCLUDED IN DUMP DESCRIPTION
-------- ---------- ---------------- -------------------------------------
UNUSED 216403 no, by default unused pages
USERPG 4433663 no, by default user process pages
BCACHE 622232 no, by default buffer cache pages
KCODE 2924 no, by default kernel code pages
USTACK 16002 yes, by default user process stacks
FSDATA 6222 yes, by default file system metadata
KDDATA 635090 yes, by default kernel dynamic data
KSDATA 352008 yes, by default kernel static data

Total pages on system: 6284544
Total pages included in dump: 1009322

DEVICE OFFSET(kB) SIZE (kB) LOGICAL VOL. NAME
------------ ---------- ---------- ------------ -------------------------
31:0x026000 1051488 16777216 64:0x000002 /dev/vg00/lvol2
31:0x026000 34278240 8192000 64:0x00000b /dev/vg00/swap2
31:0x220300 7040 8814592 64:0x700001 /dev/vgswap/lvol1
----------
33783808

[Emil Velez]

I did not see you specify a size ? I assume you created it contiguous.

Did you do a crashconf -v to see how big the dump would be. It will be smaller than your total memory since it does not dump all memory and does compression.

[PVR]

Sorry forgot to mention the size

lvcreate -C y -r n -L 8000 -n dump /dev/vg00

I created the dump logical volume based on the size suggested by crashconf ( Total pages included in dump * 4KB ). Then executed the command;
lvlnboot -d dump /dev/vg00. But it didn't reflect in the crashconf. Later executed the command as below and after that everythign working fine as expected;

crashconf -r /dev/vg00/dump

If you want to add more dumps, you should execute the following commands;

crashconf -a /dev/vg00/dump2

Thanks friends for your help.

[PVR]

Please find th esolution given above