P4300 G2 RAID vs NETWORK RAID question

[btallon]

I am setting up a new SAN with P4300 G2 two storage systems. Both are configured for RAID 5. If I understand this correctly my options to ensure data protection  are:

1) Configure both systems as a management group/ cluster and use Network RAID10 thus cutting my total storage  capacity in half.

2)Configure each system as a separate management group and use Network RAID 0 (the only option in that configuration) and use the system level  RAID 5.

I initially set up my management group and cluster with both systems and when I went to create a volume I saw that my only options for data protection were Network RAID 0 and Network RAID 10. I assume if I had a third system in the cluster, Network RAID 5 would have also been an option.

If I have my systems in a two node cluster and I choose Network RAID 0, I assume that I might lose data if one of the systems goes offline ( loss of power for example) even though the individual systems have RAID 5 configured on them.  Am I understanding this properly?

p.S. This thread ahs been moved from Storage Area Networks (SAN) (Small and Medium Business) to HP StoreVirtual Storage / LeftHand. - Hp Forum Moderator

[Bart_Heungens · Accepted solution]

Hi,

Correct with the 2 nodes in 1 MG and 1 CL, network RAID 10 will give 50% of available space... Every block of data will be written on both nodes.

In this setup you can also create a volume with RAID 0 so all data blocks are spread accross the 2 nodes; If 1 node fails (or network fails in between) you loose your volume...

For network Raid 5 you need at least 4 nodes, Raid 6 needs at least 6 nodes... That is part of the used algorithm...

Know that +95% of the existing setups are hardware Raid 5 on the boxes and on top of that network Raid 10 for the volumes...

Kr,

Bart

[btallon]

Thanks!