[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [Linux-cluster] Re: Storage Problems, need some advice

After doing much more research I came across the DS300 by IBM. It uses
SCSI drives, is fully redundant, does iSCSI and doesn't cost an arm
and a leg (just an arm). My question is, their site says linux
clustering isn't supported, but does it have to be? Doesn't iSCSI let
you do the same thing GNBD does?

hi David

do you have a link to the page with that statement? "linux clustering" is somewhat of an ambiguous term. Within the context of Red Hat software (excluding Linux Virtual Server and high-performance computing clusters), it can mean either:

a) Cluster Suite (without GFS) - only one node in a cluster accesses the storage at a time. if you fail/switch over, one node unmounts an FS, another one mounts it.

b) GFS (which implies/includes Cluster Suite) - multiple nodes accessing the same LUN with a (G)FS on top of it

I am not familiar with entry-level iSCSI initiators. I always thought iSCSI is logically like fibre, e.g. multiple hosts in the same raidgroup can concurrently access the same LUN/FS. Perhaps these entry-level iSCSI arrays are more like regular SCSI meaning that they do not support multiple initiators accessing the same LUN behind a target (storage processor).

I had a look at EMC cert matrix for the AX100/150 series arrays
thes entry-level EMC iSCSI arrays also only supports non-clustered Linux.

iSCSI will allow you to "do the same thing" as GNDB:
GNDB client and server are replaced iSCSI initiator (Linux host) and target (dedicated hardware, e.g. EMC array, or software target - not yet considered production-ready nor included with RHEL). However, if the hardware has an explicit exclusion of Linux clustering, you are stuck, not being able to have two nodes aaccess the storage at the same time..


Also, I talked to someone on their chat who said I could use any U320
drive with it, basically I could reuse the drives I already have and
just not use my old enclosure. Does that sound right? Any reason I
couldn't do that other than loosing all my data?

Anyone using a DS300? Seems like with 15k drives it would be pretty darn fast.

Linux-cluster mailing list
Linux-cluster redhat com
fn:Riaan van Niekerk
n:van Niekerk;Riaan
org:Obsidian Systems;Obsidian Red Hat Consulting
email;internet:riaan obsidian co za
title:Systems Architect
tel;work:+27 11 792 6500
tel;fax:+27 11 792 6522
tel;cell:+27 82 921 8768

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]