Configuring HP Smart Array P420i I/O Controller for VSAN

I’ve been working with many customers over the last several months and found that many are very familiar with HP hardware and just know how to set things up.  Others are looking for guidance from VMware on how to configure for VSAN.  There are things I’ve discovered that might not be obvious but can help in the VSAN setup.  Bear in mind, I am not an HP server hardware expert, so your comments are greatly appreciated.

Before I go too far, there is a bug in the HP async controller driver for the HP 420i that is included in the HP ESXi image.  The bug reduces the queue depth to 28, instead of 1020, causing poor performance in VSAN.

Here’s how to check your hosts IO Controller (storage adapter) queue depth:

  • Run the esxtop command on the ESXi shell / SSH session
  • Press d
  • Press f and select Queue Stats (d)
  • The value listed under AQLEN is the queue depth of the storage adapter

To resolve, follow these directions to implement the correct driver:

HP ProLiant Smart Array Controller Driver for VMware vSphere 5.5 (VIB file)

OK, a little background/overview on I/O Controller guidance for VSAN.  In general, VSAN recommends disabling Read and Write cache for any I/O Controller.  Since VSAN handles Read and Write caching at the software layer, there’s no need to do it at the hardware level.  Also, when destaging write cache, we want to ensure that the writes are committed to disk and not in I/O Controller cache.

In the case of the HP P420i, you cannot disable the I/O Controller cache so VSAN recommends setting it to 100% Read which essentially disables Write cache.  I recently discovered that you can also selectively pick and choose which disks to enable cache for.

Continue reading “Configuring HP Smart Array P420i I/O Controller for VSAN”

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Virtual SAN Disaster Recovery – vSphere Replication (available now) or Virtual RecoverPoint (coming soon), choose your protection!

I’m often asked how to protect Virtual SAN (VSAN). Its simple, any product focused on protecting a virtual machine (VM) will work for protecting VM’s sitting on a VSAN enabled vSphere cluster. VMware offers VDP/VDPA for backup & recovery and there are many other VMware partners with backup & recovery solutions focused on protecting VM’s. Backup & Recovery is a great way to protect data but some customers like the benefit of more granular recovery points that comes from data replication either locally or to a disaster recovery site.

To protect VSAN data in a primary site to a remote disaster recovery site VMware offers vSphere Replication (VR) to replicate the VM data sitting on a VSAN Datastore over the DR site. Of course Site Recovery Manager (SRM) is supported to automate failover, failback and testing. The VR/SRM combined solution can also be used for planned data center migrations. Here are a few great write-ups on the topics:

VMware Virtual SAN Interoperability: vSphere Replication and vCenter Site Recovery Manager

Virtual SAN Interoperability – Planned migration with vSphere Replication and SRM

VSAN and vSphere Replication Interop

One of the main benefits of VR is that it will work to replicate VM data on any storage to another site with hosts connected to any other storage. So, VSAN can be the source, the target, or both.

VSAN & VR

 

vSphere Replication can be set to asynchronously replicate every day, hour, or up to every 15 minutes. Thus providing a Recovery Point Objective (RPO) of up to 15 minutes. For many customers, this is “good enough”. For some customer workloads, asynchronous replication is not “good enough”. They need synchronous replication protection and there are several solutions in the market. One that I’ve been a big fan of for a long time is EMC’s RecoverPoint which has a great reputation for protecting enterprise mission critical data and applications.  Essentially it splits every write transaction, journals it, and synchronously makes a copy of it either locally or to a remote DR site without impacting application performance. Of course there are more details but this is essentially what it does which results in being able to recover back to any point in time. Often it’s labeled as “Tivo or DVR for the data center”. One other benefit of RecoverPoint is it can replicate data from any storage to any storage, as long as there is a splitter for the storage. EMC VNX and VMAX storage arrays have splitters built in.

The big news that just came out last week that peeked my interest is that EMC is now offering a Beta of a completely software based RecoverPoint solution that embeds the splitter into vSphere. This brings the RecoverPoint benefits to any VMware customer running VM’s on any storage: block, file, or of course even VSAN. The EMC initiative is call Project Mercury and for more information check out:

Summer Gift Part 1 – Project Mercury Beta Open!

I’m excited that VSAN customers will have a choice for data protection, asynchronously with 15 minute RPO using vSphere Replication or continuous, synchronous, and asynchronous with EMC’s Virtual RecoverPoint.

Montreal Loves VSAN!

Last week I had the good fortune to support the Montreal VMware vForum.  There were over 418 participants and 21 partner booths.  A packed house at the Hilton Montreal Bonaventure which was a great facility.

MontrealForum1

There were multiple keynote presentations throughout the day as well as break out sessions on a wide variety of topics.  In the morning session I was able to share the benefits of VSAN to the entire crowd and let everyone know about the Hands on Lab we setup for attendees to try out VSAN.

 

We setup 10 Chromebook workstations that were occupied the whole day.  A total of 86 customers took the VSAN lab and the feedback was overwhelmingly positive.  Both about VSAN and the fact that we made the labs available during the day.

MontrealForumVSANlab

At the end of the day there was an after party during which we gave away the Chromebooks to lucky winners while everyone was enjoying their favorite beverage.

A special thanks to our VMware friends, partners, and especially customers for helping make this a great day!  Montreal is a great city and now we know Montreal Loves VSAN!

I look forward to the next big event: Boston VMUG User Conference.