alternate paths and load balancing

[Doug_3]

I am going to access a xiotech san with 2 fc hba's. Does anyone have hints on best method to ensure the new vg's have load balancing as well as alternate paths? In the past I used SAM for an internal array and for an external JBOD's used pvg command line.
I have mirrored vg00 to the 2nd internal; next up will be vg02 to vg05.

Thanks in advance

[Eugeny Brychkov · Accepted solution]

Consult with xiotech SAN exptert how the best to set it up. Generally there're some ways:
1. balance 'manually': there're some LUNs within VG and you set primary path for some LUNs through HBA1 and for another LUNs through HBA2;
2. balance 'automatically': use load balancing software which also may offer more load balancing options
Eugeny

[vofsky]

Maybe secure path is best choice.

[Sundar_7]

Hi,

LVM offers you alternate path capablities but cannot load balance the IO.

EMC powerpath is a better solution which can load balance as well you can specify more than one path as an alternate path.

Sundar.

[Jim Mallett]

Alternate paths could work if you really know your data but if things are changing dynamically your best bet is to go with a 3rd party software package.
With alternate paths you may split things up nice, but over time you could end up with a bunch of hot disks running thru 1 HBA. I use PowerPath (I don't know offhand if it could be utilized in your situation) but it handles failover and the balancing dynamically.

Jim