topic Extending System file systems in Operating System - HP-UX

Extending System file systems

Jennifer Arey — Fri, 15 Sep 2000 14:13:26 GMT

I am now forced to extend most of my system filesystems. At the present time, my filesystem looks like this (using bdf)

/dev/vg00/lvol1 91669 63629 18873
77% /

/dev/vg00/lvol7 163840 134709 24984 84% /var

/dev/vg00/lvol6 344064 329808 11990 96% /usr

/dev/vg00/lvol5 32768 28526 4184 87% /tmp

/dev/vg00/lvol4 290816 282369 7521 97% /opt

/dev/vg00/lvol3 122880 92794 26769 78% /home

Everything is really full as you can see and I need to use the remaining 2GB in vg00 to extend these filesystems to reasonable levels. I read in another similar question that you should do a full backup of the lvol that you are going to extend. Is this reccommended procedure? Also any ideas on how to divided up the 2GB between the file systems would be appreciated.

Thanks

Re: Extending System file systems

Stefan Farrelly — Fri, 15 Sep 2000 14:22:12 GMT

If you have the OnlineJFS product installed (if youve bought it) you can extend your filesystems on the fly (without any downtime) and this is fully supported so you wont need to make a backup first.

If you dont have OnlineJFS then you need to unmount each filesystem in turn to use lvextned and extendfs on it. For your system filesystems should boot your system in single-user mode and then do it. You wont be able to extend / as it needs contiguous diskspace, but its a static filesystem (supposed to be!) so leave it at 77% is aok.

As for making a full backup first, just to be safe its good admin procedure to do this beforehand - and to 2 separate tapes, just in case one turns out bad. Its happened to me before! But extending filesystems is very low risk so normally I would not do this, but I would do it not long after a successfull normal nightly full backup - just to be safe.

If you have 2GB free then you dont need it all now, keep some spare for future use. I would add the following;
/var 300MB
/usr 200MB
/opt 300MB
/home 100MB
/tmp not much - maybe 100MB, yours is pretty small so 50 or so should be fine.
And keep the remaining 1 GB free for future use as and when needed.

Re: Extending System file systems

James R. Ferguson — Fri, 15 Sep 2000 14:28:28 GMT

Jennifer:

Several things to think about.

1. It never hurts to backup data. I prefer fbackup/frecover over tar or cpio.

2. If you have online JFS then you can extend on-the-fly.

3. /tmp is designed for purging. Clean it up. If you want (I don't), you can set CLEAN_TMP=1 in /etc/rc.config.d/clean_tmps to automatically delete files from the /tmp directory at bootup.

4. /var may contain old logs that can be trimmed (with SAM) and old patches that can be managed with 'cleanup' [do a man cleanup for details].

5. Search this formum for keywords like "var", "cleanup", "vxfs", "JFS", etc. You will find lots to read.

Re: Extending System file systems

Jennifer Arey — Fri, 15 Sep 2000 14:36:28 GMT

I have all hfs filesystems, so I will probably have to do the unmount thing. I guess that using SAM at this point is out of the question since I have to unmount the filesystems, huh?

I am also planning to load SAMBA on this box so I will need to create a little more space on opt or usr to accomadate that sofware.

By the way, I did not mention that the box was a K210 server running 10.20.

Thanks for the help so far.
Jennifer

Re: Extending System file systems

Jennifer Arey — Fri, 15 Sep 2000 14:40:44 GMT

Re: Extending System file systems

Tim Malnati — Fri, 15 Sep 2000 15:21:28 GMT

Where you are on HFS file systems, you will need to come down to single user mode to accomplish the task of extending these. SAM will not run with some of these file systems unmounted, so you need to learn the appropriate commands anyway.

Here is a thought. What are your plans regarding a future upgrade to 11.X? If it is relatively soon, extending the file systems will take care of things for now in 10.20. But if you plan to stay on 10.20 for a considerable period of time, it may be a better idea to bite the bullet and convert the file systems to VxFS now. This is not as difficult evolution as it sounds, particularly if you use Ignite. This can be a significant performance boost as well where there is a reasonably good chance that you have some significant fragmentation issues with file systems loaded to this extent. Be sure to perform any cleanup activities before this evolution though.

Re: Extending System file systems

Bill Hassell — Fri, 15 Sep 2000 22:47:08 GMT

2 Gb just isn't very much space at all. For filesystems more than 75% full, you should double or triple the amount currently available. Seriously, you need a *LOT* more disk space because this system is growing. Carving up the 2 Gb will buy you a few weeks at best and you'll still have to add more disk, especially using SAMBA. The assumption is that you will be sharing disks with PCs and PC users can easily fill up several gigs in a few weeks.

Look at a couple of 9 Gb disks (if you have space available in the box) or replace smaller internal disks (ie, 4 Gb) with 9 Gb disks. Disk space is incredibly sheap compared to your time and system downtime due to full filesystems.