Advice on root disk that are 18G

[Belinda Dermody]

I have a new 5470 system with the rootvg is on a 18g drive and mirrored to a 18g using UX mirror. My question, I know you are not suppose to have anything else on the root disk, but I still have 12G of space available, what type of lvols could I put out there. I am running a Unidata Database, Sybase Server(with raw lvols for db and logs) and a couple of Large volumes that hardly ever change only are read. I am moving things off of a K200 which had a bunch of 4g drives.

[Hai Nguyen_1 · Accepted solution]

I had the same as you for my rp5450. What I did was I created a STATIC filesystem /apps for Oracle executables and other non-hp apps.

Hai

[Steven E. Protter]

I advise against putting oracle data on there. It would have to be part of vg00 and would make Ignite backups more complicated and a pain in the posterior tushie.

What I do with my free space is as follows:

I have two 73 GB disks and everything in vg00 is mirrored, even swap and dump. The leftover is allocated to /images which amounts to 95 GB on my production systems.

Most of that space I use for Ignite make_net_recovery images. All my servers write these servers to each other so if one box goes really bad, putting it back to gether is as easy as booting the replacement box off one of the other Ignite servers.

I also reserve a few GB for myself via samba mount, because the diskmasters at work are demanding we clear space off Microsoft Servers. I store patches, patch depots on the HP-UX boxes out of reach of the dasterdly disk auditors.

SEP

[GK_5]

If you have other disk for unidata and other stuff, I'll stay away from using diskspace from rootvg.

[Vitek Pepas]

I wouldn't put any data that is actively used on rootvg. Even it is read only, it may have impact on performance. Plus, you need to consider OS backups - you don't want large amount of data stored there.

[Rodney Hills]

I would think you could create a new lvol on vg00 and put any low use files and their wouldn't be any impact on performance.

I have similar situation and I mirrored half the drive for the "root" file systems. The rest I use to store "depot" files I download from the internet.

HTH

-- Rod Hills

[Patrick Wallek]

Resist the temptation to try to use all the space on those drives. You really don't want to do that.

Don't consider it wasted space now, consider it as future expansion. If you ever need to expand /var, /opt, /usr, /home, then you want the space to be available to you. Also keep in mind that new releases of an OS are NEVER smaller than the previous release. They always seem to need more space, so you want the extra breathing room for upgrading the OS in the future as well.

The only things I MIGHT consider putting on the OS drives would be the binaries for your DB's. Do NOT put any database data on those drives. Just don't do it.

Also, since this is a new machine, make SURE you install Ignite/UX and take regular make_tape_recovery or make_net_recovery backups of this machine. If you should ever completely hose the OS, you want the speedy recovery an Ignite/UX backup offers you.

[A. Clay Stephenson]

If this were me, I'd leave it alone. I know that that useless 12GB is killing you but the advantages of a lean mean vg00 outweigh the "wasted" disk. You'll be surprised how full /var can get if you keep several patch revisions; /opt can need quite a bit of space; and /usr will grow a bit as well. For many years, I've resisted the temptation to put anything but system stuff in vg00. You will find the unused space very helpfull if you suddenly need to expand some LVOL's. Moreover, OS upgrades becomes much easier if only system stuff is in vg00. After upgrading or cold installing an OS you can simply vgimport and you are good to go --- if there ain't nothing else in vg00.

Knowing fully well that you are going to ignore this advice, the ONLY things that I would consider
are the binaries associated with an application (e.g. the database executables and libraries).

[James R. Ferguson]

Hi:

My vote too, is to leave vg00 for the operating system and its standard logical volumes and filesystems. If you keep a large amount of performance data from 'glance' /opt may need to be resized. There is rarely engough space in the minimal configurations of '/var' and '/tmp'. '/var/tmp' is intended for application temporary files. '/var/adm/sw' grows substantially as patches are applied (although a great deal of space can be reclaimed with 'cleanup'). '/tmp' can be made quite large too, to accomodate software depot construction with 'swcopy'. Too, unsharing ('sh') patch files places the patch in '/tmp' so it is convenient to have a large workspace when you need it.

Storage aside, you don't want to have a great amount of I/O from any applications pounding on the root volume group. This can degrade performance.

The isolation of the OS on vg00 make making Ignite recovery tapes easier and cleaner. If you need to re-install or clone your system, the isolation of applications on non-vg00 volume groups makes this task simple.

Disks are relatively inexpensive, and worrying about fully utilizing vg00 is needless when compared to the benefits of keeping only your operating system on it.

Regards!

...JRF...

[Belinda Dermody]

Thanks for all the responses and it was what I expected and it made my decision easier, sorry to say Jim you are wrong I will not put anything out on the root disk, I am coming off a system that had 72G to this one with 144 so I have plenty of spare room and plus I can keep my 70% free space threshold available. The left over 12g will be used for expansion, I only have 2 cpus now, hope to get two more and more memory in the future.

As always this forum has come up with great answers and diversified ones, keep up the good work.

[TOMAS BERNABEU]

Ignite server repository would be a good idea.

Tom