How can I safely trim down /dev ?

tigermusti · 12-12-2002, 01:18 PM

I'm relatively new to Linux, so I hope you can help me out with this one.

I would like to run mondo on my RedHat 8.0 but I need about 30m extra free
space in my root directory, /usr , /home , /var /tmp are all under LVM in
their own logical volume. (/usr=ext2, /home=ext3, /var=reiser /tmp=reiser)
So I need to get this space by trimming down /dev , its a 114meg.

The problem is that I don’t know wich devices I REALY need (is $ls -l
--time=atime a safe way to determine this ?)

Or is there a better way to filter them ?

I also noticed that it's not possible to 'cp' a device is their any way I
can copy them so I could include them on a boot-disk generated by 'mindi'
(in case things go wrong) what about the sym-links ?

Can I loop-mount an iso image of a bootdisk ( is this safe to do or wil it
start booting my system again and/or worse ? ) I would like to edit the
included /etc/fstab so that I can use my second cd reader too (:

acid_kewpie · 12-12-2002, 01:25 PM

114mb??!?! that is not possible. the entries in the /dev/ directory are not even really files, they have no size. if you have more than 1mb in there you have had somethign go very wrong.

i have 15252 entries in /dev, taking up a grand total of 332kb, made up of directory entries (4kb block) and some very basic system scripts.

trickykid · 12-12-2002, 01:33 PM

The /dev directory is a pseudo type file system, it shouldn't take up rarely any space at all. The files in there are basically only links to hardware devices on your system.

How are you getting the output that /dev is taking up 114 megs of space ?? But my advice, don't remove anything in that directory, it could make your system non-functional.

Thymox · 12-12-2002, 01:33 PM

If you don't believe him, then go to your /dev directory and issue the command du -ch ./ This lists every 'file' in there, how much space it physically takes up, and then totals it at the end for you. My system lists it as follows:

Code:

0       ./cpu
... (to many to list)
0       ./sg
0       .
0       total

acid_kewpie · 12-12-2002, 01:37 PM

this whole "deleting dev entries" seems to have suddenly become really popular this last week huh?

tigermusti · 12-12-2002, 01:38 PM

Yes I seems that I'v made a mistake , sorry for that to you all if i perform
du -hc /dev | tail -1 then i get a more modest 339

trickykid · 12-12-2002, 01:39 PM

Quote:

Originally posted by acid_kewpie
this whole "deleting dev entries" seems to have suddenly become really popular this last week huh?

I was thinking the same thing myself. Maybe we should post a good howto on the Linux Filesystem..

Thymox · 12-12-2002, 01:40 PM

It is understandable from some points of view... it can be annoying and confusing having so many entries in there, when the majority will not be used. That is why I love devfs! It is a God send! Unfortunately, unless people have already experienced it, or are told about it, they will largely be unaware of devfs, and so 'removing entries' seems quite logical... even if potentially fatal!

tigermusti · 12-12-2002, 01:51 PM

Oh damn I've been so stupid !! IT WILL NEVER HAPEN AGAIN ! but still than ks for the reactions.

MasterC · 12-12-2002, 04:33 PM

Most things here seem to go in trends though, someone will read a thread, see how things go, run into problems and post similar questions regarding things they tried. It takes 1 or 2 coincidental similar questions to start the ball rolling, then it's a full on hit of very related questions, just like the "linux uses all my memory" questions that come and go.

Cool