topic Re: dynmaic disks on Linux AS 2.1 in Operating System - Linux

dynmaic disks on Linux AS 2.1

RAKESH_12 — Wed, 14 Jan 2004 09:13:15 GMT

hello linux experts,

I have been tasked with the installation of a new SAN based on RH LINUX AS 2.1.

I am unsure on how to setup / convert / administrate "dynamic disks" for linux. (Is this similar to W2K dynamic disk setup)

Please let know your thoughts.

Thanks in advance

Rak

Re: dynmaic disks on Linux AS 2.1

Paulo A G Fessel — Wed, 14 Jan 2004 09:19:17 GMT

The best way is download and install LVM from http://www.sistina.com. As I don't know how proficient you are in Linux, I suggest you to use the LVM1 as RHAS 2.1 provides the driver for it but not the userland tools. Go figure.

Also, get the latest 2.4.20 kernel available for RHAS - it has a faster SCSI layer than 2.4.9 versions, even recent ones patched by RH. You may have to recompile your kernel to scan all SCSI LUN's in your system.

You'll be able to find more details on the LVM HOWTO:

http://tldp.org/HOWTO/LVM-HOWTO/

HTH
Paulo Fessel

Re: dynmaic disks on Linux AS 2.1

RAKESH_12 — Wed, 14 Jan 2004 09:23:23 GMT

Paulo,

Many thanks for the info....!... i will try the install of LVM and use trial and error.

Are there any other hints - tips you may have when installing a SAN with linux??

Thanks again.

Raks

Re: dynmaic disks on Linux AS 2.1

Paulo A G Fessel — Wed, 14 Jan 2004 11:37:05 GMT

My only experience is with EMC, so I don't know how much my experience applies to you.

I don't know which adapters you're going to use; here where I work we use Emulex adapters for our Linux servers. The most important parameters are the topology, link speed and timeout.

Be sure to select the correct topology, or you won't be able to connect to the SAN at all. Ditto for the link speed supported by your cards/switches/disk arrays etc...

About the timeout, it is important because when you reconfigure the EMC array all the devices become inaccessible during a brief period. You so should configure your timeout to be larger than this time period - again, follow the directions of your storage manufacturer.

It is possible to add more disks to Linux without rebooting the box. Just issue an "echo add-single-device ". I think these are sufficiently self-explanatory. ;-)

Good luck,
Paulo Fessel