Dump command hanging

usao · 10-12-2015, 08:41 AM

Ive noticed the past several days the dump command has been hanging and not producing any output.
I tried to run from the command line, but it's not doing anything and requires a "kill -9" to abort from another console.

# /sbin/dump -0uz9 -f /tmp/root.151012.L0.dump /

Output file is created, but 0 length, even after several hours. This has been running fine for almost a year until this weekend...

pan64 · 10-12-2015, 08:47 AM

you may try strace to check what's happening

usao · 10-12-2015, 08:58 AM

strace shows it hanging when it tries to access "dm-14".

open("/dev/dm-13", O_RDONLY) = 5
lseek(5, 1024, SEEK_SET) = 1024
read(5, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 136) = 136
close(5) = 0
open("/dev/dm-14", O_RDONLY) = 5
lseek(5, 1024, SEEK_SET) = 1024
read(5,

However, there is no /dev/dm-14 that im aware of. I looked in /dev/disk/by-id and didn't see any dm-14 listed.

pan64 · 10-12-2015, 09:01 AM

probably an improperly umounted/detached device, I have no idea. Maybe a reboot helps?

usao · 10-12-2015, 09:10 AM

Yes, it does look like this device might be an issue.
dmsetup shows that to be used as a RAW device, and I tried to access the /dev/raw device and it's also hanging.
Ill have to see what's wrong with the device on the SAN, but as a side-note, why would it hang on access to the raw device when it's not dumping the raw device in the command itself?
I requested it to dump a filesystem, which has nothing to do with the raw device.

pan64 · 10-12-2015, 09:38 AM

any access to that device will hang because the driver is out. You may try to access the filesystem on that device, partition table or whatever ("high" level access - not only to the raw device) and finally all of them will hang. I have no idea about your system at all, but probably something was "in use" on that device.

usao · 10-12-2015, 09:39 AM

Ill see if I can schedule a reboot. Thanks.