specify the stripe LVM during cold installation

[Karthik S S]

Hi Emily,

Striping (RAID0) :
a. Better Read Performance ( Data is spread across multiple disks )
b. Better Write Performance ( Data can be written in multiple disks simultaneously )
c. Not fault-tolerant ( One disk fail and the whole volume fails )

Mirroring (RAID1) :
a. Best read performance ( Data can be read from the actual disk and from Mirrored disk as well )
b. Degraded write performance ( As it has to write the same data physically on to 2 disks (2 is minimum but you can have more) )
c. Fault tolerant ( One disk fails but you have the data on mirrored disk)

Now coming back to IUX Server. IUX Server is typically only read intensive. Hence the better option is to go for mirroring as it offers the best read performance and the meantime fault tolerance.

Hope this answers your question

Regards,
Karthik

[Pete Randall]

I do recall that there used to be an option during install to choose a striped layout for vg00, assuming you had more than one disk available. This was back in 10.20 on 700 series workstations. I don't know if such a thing is available for 11.x on servers or not.


Pete

[Pete Randall · Accepted solution]

Further investigation indicates that this option is no longer available as of 11.0. The File System options you can select from are: "Whole Disk (not LVM); "Logical Volume Manager (LVM) with HFS"; and Logical Volume Manager (LVM) with VxFS.


Pete

[Mark Landin]

If you are talking about LVM striping, then you stripe a logical volume, not the entire volume group. You can easily set LVM striping up on a logical volume in the same area that you set HFS vs. JFS.

Note that even though you have enough disk space, sometimes you can't stripe a logical volume because the HP-UX installation utilities that configure the logical volumes will process them in alphabetical order based on their mount directory names. If you wanted to stripe /tmp, for instance, it will get built AFTER /, /opt, and /etc, and put them all on the primary (boot) physical volume. When it's time to build /tmp, though, you may not have enough free disk space on your primary disk to put half of /tmp on it.

In any case, LVM striping CAN be done, and while it may not be as performant or safe as Mirror Disk, it is vastly cheaper. :)

[emily_3]

Thanks for your suggestions.
For my situation, mirror disk is impossible, because I couldn't put everything into one disk, while the other one is purly mirror. Because one disk don't have enough space to contain everything.

So maybe it's the time to upgrade the hardware to archive high performance.