topic Re: disk configuration in Operating System - HP-UX

disk configuration

I.Delic — Mon, 13 Oct 2003 08:05:08 GMT

Hy guy's,
Ik have to configur one UNIX box and i don't know
which sulutions ik have to choose.I wil use this machine for our database.
Please look in my attachment en give me one good advice.
I like to hear something about wy do ik have to use solution A of solution B.
Thank you

Re: disk configuration

Jakes Louw — Mon, 13 Oct 2003 08:17:11 GMT

How about solution C:

Primary -> Mirror
c0t2d0 -> c1t2d0
c1t3d0 -> c0t3d0
c1t4d0 -> c2t4d0
c2t5d0 -> c1t5d0

This will give you optimum usage of each channel for your config.

Re: disk configuration

Michael Steele_2 — Mon, 13 Oct 2003 08:20:55 GMT

In both cases you'll be building in a disk bottleneck.

O/S disks are always the busiest and you want these on isolated disk controllers. One controller each with nothing else on it. If possible.

In your examples you've got either four disks on one O/S disk or the other O/S disk. Same thing. Same built in disk bottleneck.

Buy another controller or two for better performance.

Re: disk configuration

Alzhy — Mon, 13 Oct 2003 08:21:11 GMT

I assume c0 and c1 are the on-board SCSI controllers (UW-SCSI?) and c2 is a PCI HBA... If c2 is a much faster controller (U160/320?)and you employ fast SCSI disks -- then it would be better if you add another similarly fast HBA as c2.
.
IMHO, Solution A and Solution B will make no difference in terms of performance as the mirrors will adjust to the slowest controller's ability to serve out the disks...

Re: disk configuration

Alzhy — Mon, 13 Oct 2003 08:27:03 GMT

BUT, if this is just a small application (either web serving or a smll Database or File Server or lioght development).. then this should be sufficient.. Some occasional hiccups will be expected but you can go with this config...

Re: disk configuration

Stefan Farrelly — Mon, 13 Oct 2003 08:29:19 GMT

Solution A offers no vg01 primary data on the same disk as the operating system - which is always a good thing as c0t0d0 is always going to be a busy drive and you need good response time on it for HP-UX to perform well.

Solution B offers a bit more of a balance, primary data for Vg00 and Vg01 on 2 disks each - but I would go for solution A - never put any application data on the same disk as your main Vg00 disk/boot disk.

Re: disk configuration

I.Delic — Mon, 13 Oct 2003 09:09:28 GMT

hi,

Iâ m little beat confused. Now I donâ t know nothing. Kan you check mij ioscan â f to see how many controllors do ik have ?

I thing 3 but please tel me if iâ m wrong. We dont have mony to by onother controlor.

Thank you

/dev/dsk/c1t1d0 ----- i dontâ s se this in my ioscan â f

Sorry my english is not very

Re: disk configuration

I.Delic — Mon, 13 Oct 2003 09:36:25 GMT

Iâ m little beat confused. Now I donâ t know nothing. Kan you check mij ioscan â f to see how many controllors do ik have ?
I thing 3 but please tel me if iâ m wrong. We dont have mony to by onother controlor.

Thank you

/dev/dsk/c1t1d0 ----- i dontâ s se this in my ioscan â f

Sorry my english is not very

Re: disk configuration

Michael Steele_2 — Mon, 13 Oct 2003 11:04:42 GMT

If c0t4do and c2t5d0 are your O/S then think about moving c0t8do and c2t9d0 out to another controller. This puts the two busiest disks on the system into dedicated controllers.

You can't move c0t8do and c2t9d0 onto c1 because you end up with the potential for another disk bottleneck and worse, a single point of failure at the c1 SCSI controller.

So try what you've got unless you can get another SCSI controller for fault tolerance. For unless you have an idea about your file system structure and which file system will be most written too, I believe either config will probably work as well as the other from a performance objective.

So keep fault tolerance in mind until you can get another SCSI controller.

##########################################
# SCSI c0tYdZ plus two disks
#
# c0t4d0 and c0t8do
##########################################

ext_bus 0 8/4 c720 CLAIMED INTERFACE GSC add-on Fast/Wide SCSI Interface
disk 0 8/4.5.0 sdisk CLAIMED DEVICE SEAGATE ST34573WC
disk 1 8/4.8.0 sdisk CLAIMED DEVICE SEAGATE ST34572WC

##########################################
# SCSI c1tYdZ plus three disks
#
# c1t5do, c1t8d0 and c1t13d0
##########################################

ext_bus 1 8/8 c720 CLAIMED INTERFACE GSC add-on Fast/Wide SCSI Interface
disk 2 8/8.5.0 sdisk CLAIMED DEVICE SEAGATE ST34371N
disk 3 8/8.8.0 sdisk CLAIMED DEVICE SEAGATE ST34573WC
disk 7 8/8.13.0 sdisk CLAIMED DEVICE SEAGATE ST39236LC

##########################################
# SCSI c2tYdZ plus two disks
#
# c2t5d0 and c2t9do
##########################################

ext_bus 2 8/12 c720 CLAIMED INTERFACE GSC add-on Fast/Wide SCSI Interface
disk 4 8/12.5.0 sdisk CLAIMED DEVICE SEAGATE ST34573WC
disk 8 8/12.9.0 sdisk CLAIMED DEVICE SEAGATE ST39236LC

Re: disk configuration

I.Delic — Mon, 13 Oct 2003 11:42:37 GMT

Hi Michael,

I have 8 disk's.

Thank you