Legacy HDS Forums

LDEVs, LUSEs, Open-V etc

Discussion created by Legacy HDS Forums on Aug 29, 2007
Latest reply on Sep 4, 2007 by Legacy HDS Forums

Originally posted by: Optic

Hi All,

I know this is a bit of a lame question, but I was hoping to get some guidance anyway.  I don't expect anyone to feed this to me on a platter - even just a pointer to a HDS best practices guide or something like that would be great.

I have inherited configuration duties on our company SAN which is a Lightning 9970V.  While I am used to modular SANs, this enterprise stuff is new to me.  We are about to upgrade to an NSC55.

I was shown how to do all the normal day to day stuff (presenting LUNs to hosts, putting a new host on the SAN etc) and I am comfortable with it.  My real problem is that while I can do it, I don't really understand what I am doing (if that makes any sense).

When our HDS was initially configured, all the LDEVs were created in 20GB chunks.  We then create a LUSE of the required number of LDEVs and then present this LUSE to the host.  I have seen references on these forums of people avoiding the use of LUSEs.  Is our configuration bad?  What is "normal"?  Do most people split up all their storage into a standard size LDEV right from the start, or is it more normal to create each LDEV as it is needed?

What is Open-V?

Whenever we add a new host to the SAN, we essentially pick a random port to zone the new host to.  I have no idea which of our ports might be highly utilised, and which ones aren't.  Is there a way to tell?

What is a CU?  Again - I can see that each LDEV seems to live under a "CU", but I don't understand the concept of a CU, why they exist, why an LDEV needs to live under a CU etc etc.

Any and all help greatly appreciated!