Only 2 Controllers to implement Multi site HA/VMWare with HP P4000

[RafaelBianchini]

Hi all,

I want to know if I can implement a multisite HA/VMWare olution using P4000 with only 2 controllers.

I will put each one controllers in each site, and implement Network RAID 10.

Is it possible ?

Regards.

Rafael Bianchini

P.S.This thread has been moved from Storage Area Networks (SAN) (Small and Medium Business) to HP StoreVirtual / HP LeftHand Storage- HP Forums Moderator

[Northwoods]

Yes you can. However, you'll also need to implement a virtual FOM instance for best practice and to keep the SAN up if a node goes offline.

[oikjn]

if this is really just for DR and you are thinking about it just because the features are included for free with the SAN/iQ software, I would advise you read the multi-site HA/DR readme first and then read it again.  A multi-site cluster, while available with the software you purchased, adds significant complications to your setup.  You really need three sites (the third can be a cheap hosted site w/ minimal bandwidth, but you really do need that third site) and bandwidth and latency between your two main sites become a major concern and any interruption to that will interrupt your SAN. 

Look at remote snapshot replaction before going to a multi-site san and only go to the multi-site option if you 100% have to have 100% uptime.  If you go remote snapshot, best practice is to run two management groups so you don't have to worry about multi-site quorum as well.  You can still do a good DR solution w/ remote snapshots with failover as well.

[RafaelBianchini]

Thank you for your reply.

I'm looking for other information about this solution. Can you help me ?

I intend put one VMWare ESXi host more one P4300 Controller, with 7.2 Tb, in each local (2 sites in this case) and establish a Network RAID 10 with a dedicated and redundant optical fiber.

So, after i will configure VMWare HA to complete the DR and High Avaiability solution.

What do you think about this ? And the FOM, is it realy necessary in this case ? Remember, i will use only 2 controllers (enclousers) ( not 4 - 2 per site).

Basicaly, my project is (the SAN part) :

Site A                                   Site B

Host ESXi A                         Host ESXi B

 | |                                          | |

SW ------------FO------------- SW

 | |                                          | |

P4000 A                              P4000 B (just 1 controller per site)

Please, make comments.

Best regards.

[oikjn]

read the manual and HA guide as listed on the P4000 software page.  It will answer all of your questions.

Yes you must have a FOM and technially a 3rd site.  Think about a failover solution and how it will be handled.  Control of the cluster is handled through a voting quorum... it is impossible to get a majority vote with TWO members, the minimum needed is three which means a FOM for automatic failover or a virtual manager for manual failover, but if you are actually trying to do a multi-site cluster, you would be totally contradicting yourself if in one breath you say you require multi-site and the other breath you say I'm ok with manually restoring quorum.

Why do you think you need a true multi-site cluster and not just go with using remote replication for DR?

[RafaelBianchini]

I'm thinking about P4000 multisite because i want to delivery a automatic failover / dr project whithout VMWare SRM.

[oikjn]

really read that HA manual HP provides.  The multi-site feature is included with the Lafthand software, but the cost for you to actually impliment it successfully is typically much more significant.  Have you considered latency/bandwidth/uptime of your VPN?  Those costs typically make multi-sites a no-go for anybody who is thinking about doing it just because its available. 

The HA/DR manual from HP is very complete with what is needed so it shoudl answer all of your questions.  The critical issue is that you cannot skimp on the latency/bandwith to the remote site as that is likely to be your slowest point in the system and for a multi-site cluster the data has to be written to both before the write is confirmed.