topic shell script in Operating System - Linux

shell script

Leovino A. Trinidad, Jr — Fri, 01 Aug 2003 10:20:32 GMT

Hi!

How can you detect/check which drive (dev/hda or /dev/hdc) is up using a script?

I'm making an offline disk mirroring script using dd command. Offline disk mirroring in the sense that the mirroring is a scheduled type of backup (not like the usual one which is a realtime mirroring - to avoid crashes when certain patch is applied and it can boot either of the drives at once).

Hope you can help me.

Regards

LAT

Re: shell script

Francisco J. Soler — Fri, 01 Aug 2003 10:46:10 GMT

Hi LAT,

For be up, do you mean mounted?

If so, you can try this one:

ACTIVEA=`df | grep /dev/hda | wc -l`
ACTIVEC=`df | grep /dev/hdc | wc -l`

If ACTIVEA is 0 (zero) there is nothing mounted in /dev/hda, the same for ACTIVEC

HTH
Frank

Re: shell script

Leovino A. Trinidad, Jr — Fri, 01 Aug 2003 12:53:29 GMT

Re: shell script

Caesar_3 — Fri, 01 Aug 2003 16:05:34 GMT

Hello!

Lets say that this depend on the shell
that script is for (sh/bash/csh/ksh)

And yes you can do this.

Caesar

Re: shell script

Francisco J. Soler — Fri, 01 Aug 2003 16:07:44 GMT

Hi LAT,

If you don't want a sting value, your correction is right. Good correction.

On the other hand FYI, you can obtain useful information about the system in the virtual /proc file system. For example, if you issue:

cat /proc/modules, you get information about loaded kernel modules. Or

cat /proc/meminfo, you get information about the used memory in the system.

Or about the partitions you have "used" you can type: cat /proc/partitions and pipe the output through a grep like in df command.

Regards.
Frank.