Anyway to config crash/diskdump with an LVM Swap?

epoh · 09-08-2009, 11:12 AM

I've got a box that's been rebooting itself and we are trying to determine why. I'm trying to config diskdump, but the problem I've got is there's no available local space on the box, and swap is an LVM partition (I was not the one that built the box, sadly.) I'm guessing there's no way to configure diskdump to utilize an LVM partition? Any suggestions would be greatly appreciated.

OS: RedHat Enterprise Linux ES 4
Kernel: 2.6.9-34.ELsmp x86_64
Installed: diskdumputils-1.4.1-7.x86_64.rpm & crash-4.0-5.0.0.2.x86_64.rpm

The other issue, I'm not certain scsi_mod is supported:

Quote:

bash-3.00# lsmod
Module Size Used by
zlib_deflate 24281 0
md5 5697 1
ipv6 282785 570
autofs4 23753 0
i2c_dev 13633 0
i2c_core 28609 1 i2c_dev
nfs 243825 5
lockd 77809 2 nfs
nfs_acl 5185 1 nfs
sunrpc 174905 9 nfs,lockd,nfs_acl
dm_round_robin 4929 1
dm_multipath 21841 2 dm_round_robin
sr_mod 20581 0
usb_storage 70793 0
joydev 11841 0
ohci_hcd 24273 0
hw_random 7137 0
e1000 113837 0
dm_snapshot 18689 0
dm_zero 3649 0
dm_mirror 29017 0
ext3 137809 5
jbd 68977 1 ext3
dm_mod 67457 13 dm_multipath,dm_snapshot,dm_zero,dm_mirror
qla2300 127360 0
qla2xxx 333504 13 qla2300
qla2xxx_conf 303240 1
mptscsih 2753 0
mptsas 11981 3 mptscsih
mptspi 11725 1 mptscsih
mptfc 10825 1 mptscsih
mptscsi 46161 3 mptsas,mptspi,mptfc
mptbase 64609 4 mptsas,mptspi,mptfc,mptscsi
sd_mod 19393 9
scsi_mod 140561 8 sr_mod,usb_storage,qla2xxx,mptsas,mptspi,mptfc,mptscsi,sd_mod

cardy · 09-09-2009, 10:16 AM

This may not be exactly what your looking for but if the box has a serial port on it you could do the following, I have used these steps to diagnose kernel crashes before:

* Buy a Null Modem cable
* Link the null modem cable between the server thats crashing and another machine (this second machine will require some terminal software (minicom on linux, hyperterm on windows))

* Add the following to the grub.conf on the end of the appropriate kernel line your booting from

Quote:

console=tty0 console=ttyS0,9600n8

So this

Quote:

title Red Hat Linux (2.4.9-21)
root (hd0,0)
kernel /vmlinuz-2.4.9-21 ro root=/dev/hda6
initrd /initrd-2.4.9-21.img

would becomme this

Quote:

title Red Hat Linux (2.4.9-21)
root (hd0,0)
kernel /vmlinuz-2.4.9-21 ro root=/dev/hda6 console=tty0 console=ttyS0,9600n8
initrd /initrd-2.4.9-21.img

This will cause console output to be logged to the serial port as well as the main display. Finally set the second machine to log any data received from the serial port to a file. You may be able to push the serial port speed higher if you need that 115200 for example as a baud rate.

If the system crashes after this the second machine should capture any output about the crash.