Primary And Alternative Link On HP AutoRaid

[westpanda]

1. In HP AutoRaid, how can I identify which Controller(X and Y Controller) is the primary controller?

2. How can I execute vgcreate command to create VG using primary link device name?

3. In HP VA7100 Disk Array, I use lvcreate -i -I(stripes) argument to create logical volume. Is it necessary?

[James Murtagh]

Hi,

1) Not sure if you are talking about software here but in lvm vgdisplay will show which device is currently the primary and its alternate link below it. You can change this using "pvchange -s " but on vg activation the primary will be reset to the order the devices are presented in /etc/lvmtab.

2) Just use :

# vgcreate

If you wanted to add the alternate link do so after the primary device, or use vgextend after its been created.

3) I'm not sure what raid mode the VA will default to or what you have it set to but I doubt you need striping. Still, only testing and an application performance profile will determine this.

cheers,

James.

[Sunil Sharma_1]

Hi,

1. I think you can use amdsp (HParray manager comamnd) to see the primary controller.
2. there is no difference in primary and secondary link as such. You can use any link and create volume group and whichever you use in creating voulme group that will becom primary link and another will secondy. You have to do vgextend to configure secondry link.
3. It is not necessary to use lvcreate -i -I .( these option is for creating striped volumes)

Sunil

[Charbel Bou-eid]

Hi,

1- The easiest way to identify which is the primary controller is to check it for the AutoRaid control panel by Pressing the following key sequence:
Menu, - , Enter , +
and read the Primary Cntrl value.

The other way is to issue "#arradsp -c $sn" , where "sn" is a variable that contains the serial number of the AutoRaid. You can get it either from the control panel or with "#arraydsp -i".

2- Please note that the Primary Cntrl on the AutoRaid does not impose the primary path (or link) of a volume group/logical volume. It is only imposed by the way you create it.
#vgcreate /dev/vgxx <1st device file : will be primary link> <2nd device file : will be alternate link> . You are the one who decide which device file to use first (as primary link).

3- The VA7xx0 family of Virtual Arrays comes by default (factory) with AUTORAID mode, so need to use any stripe option when creating a LV on the VA.

Hope the above will help.

Charbel

[Rgomes]

HI,

VA7110 only has one redundancy group( RG), so 2nd controller is only for redundancy but not for I/O seperation.

You can also get the primary and alternate path from ioscan output after creating LUNs.

regards,
Richard