Can I remount '/' partition without a reboot?

benr77 · 08-19-2006, 01:01 PM

I have a server with the following partitions configured:

Code:

Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/hda2             78234008   2242520  72017376   4% /
/dev/hda1                99043      8004     85925   9% /boot
none                    111368         0    111368   0% /dev/shm

I want to add quota support to the / partition, which requires the I modify /etc/fstab and then remount the partition in question. Can I remount this partition using:

Code:

mount -o remount /

Will this cause any problems considering the mount program itself is located on the partition which is being remounted? I'd like to do this without rebooting the machine if at all possible.

Thanks

AAnarchYY · 08-19-2006, 04:16 PM

Yes, you can remount the root partition without rebooting with that command. Shouldnt have any problems.

benr77 · 08-19-2006, 04:32 PM

Thanks AAnarchYY.

What would happen if the remount failed for any reason? I assume then the system would be left without access to any binaries, and then require a reboot. Is this correct?

mkirc · 08-21-2006, 09:50 AM

Mount a CD with a Linux first, in case of problems remounting /-Filesystem you have at least the CD-Commands to work with.
Maybe you can solve the potential issue and remount the /-Filesystem then manually !

benr77 · 08-21-2006, 09:55 AM

I'm not able to mount a Linux CD as this is a remote system.

I suppose I could copy a set of useful binaries to a temporary location on another partition instead.

AAnarchYY · 08-21-2006, 03:02 PM

or if your looking to save space, throw busybox on a little loop device and then give it a shot. it should have all the commands you need.

benr77 · 08-21-2006, 03:04 PM

Yes, thanks. I'd forgotten about busybox - I'll do exactly as you suggest. Cheers!

mkirc · 08-22-2006, 12:12 AM

My I ask: What is busybox ?Sounds interesting !?

benr77 · 08-22-2006, 01:26 AM

Busybox is a collection of many unix utilities - it's designed for embedded systems with restricted resources. Each tool has cut down options, but includes the commonly used ones which still behave exactly like their GNU counterparts.

What is can be used for however, is mounting on a loopback device to provide a local copy of system tools that takes up little space - great for situations such as mine where I'm need to remount / or /usr on a remote system where I'm keen to avoid a reboot - and busybox would give me access to the mount command if my remount failed and I was unable to access the system mount binary.

http://www.busybox.net/about.html