Alert: vSphere 5.5 U1 and NFS issue!

Some had already reported on this on twitter and the various blog posts but I had to wait until I received the green light from our KB/GSS team. An issue has been discovered with vSphere 5.5 Update 1 that is related to loss of connection of NFS based datastores. (NFS volumes include VSA datastores.)

This is a serious issue, as it results in an APD of the datastore meaning that the virtual machines will not be able to do any IO to the datastore at the time of the APD. This by itself can result in BSOD’s for Windows guests and filesystems becoming read only for Linux guests.

Witnessed log entries can include:

2014-04-01T14:35:08.074Z: [APDCorrelator] 9413898746us: [] Device or filesystem with identifier [12345678-abcdefg0] has entered the All Paths Down state.
2014-04-01T14:35:08.075Z: [APDCorrelator] 9414268686us: [] Device or filesystem with identifier [12345678-abcdefg0] has entered the All Paths Down state.
2014-04-01T14:36:55.274Z: No correlator for vob.vmfs.nfs.server.disconnect
2014-04-01T14:36:55.274Z: [vmfsCorrelator] 9521467867us: [esx.problem.vmfs.nfs.server.disconnect] 12345678-abcdefg0-0000-000000000000 NFS-DS1
2014-04-01T14:37:28.081Z: [APDCorrelator] 9553899639us: [] Device or filesystem with identifier [12345678-abcdefg0] has entered the All Paths Down Timeout state after being in the All Paths Down state for 140 seconds. I/Os will now be fast failed.
2014-04-01T14:37:28.081Z: [APDCorrelator] 9554275221us: [] Device or filesystem with identifier [12345678-abcdefg0] has entered the All Paths Down Timeout state after being in the All Paths Down state for 140 seconds. I/Os will now be fast failed.

If you are hitting these issues than VMware recommends reverting back to vSphere 5.5. Please monitor the following KB closely for more details and hopefully a fix in the near future:


Disk Controller features and Queue Depth?

I have been working on various VSAN configurations and a question that always comes up is what are my disk controller features and queue depth for controller X? (Local disks, not FC based…) Note that this is not only useful to know when using VSAN, but also when you are planning on doing host local caching with solutions like PernixData FVP or SanDisk FlashSoft for instance. The controller used can impact the performance, and a really low queue depth will result in a lower performance, it is as simple as that.

I have found myself digging through documentation and doing searches on the internet until I stumbled across the following website. I figured I would share the link with you, as it will help you (especially consultants) when you need to go through this exercise multiple times:

Just as an example, the Dell H200 Integrated disk controller is on the VSAN HCL. According to the website above it is based on the LSI 2008 and provides the following feature set: 2×4 port internal SAS, no cache, no BBU, RAID 0, 1 and 10. According to the VSAN HCL also provides “Virtual SAN Pass-Through”. I guess the only info missing is queue depth of the controller. I have not been able to find a good source for this. So I figured I would make this thread a source for that info.

Before we dive in to that, I want to show something which is also important to realize. Some controllers take: SAS / NL-SAS and SATA. Although typically the price difference between SATA and NL-SAS is neglectable, the queue depth difference is not. Erik Bussink was kind enough to provide me with these details of one of the controllers he is using as an example, first in the list is “RAID” device – second is SATA and third SAS… As you can see SAS is the clear winner here, and that includes NL-SAS drives.

mpt2sas_raid_queue_depth: int
     Max RAID Device Queue Depth (default=128)
  mpt2sas_sata_queue_depth: int
     Max SATA Device Queue Depth (default=32)
  mpt2sas_sas_queue_depth: int
     Max SAS Device Queue Depth (default=254)

If you want to contribute, please take the following steps and report the Vendor, Controller type and aqlength in a comment please.

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

The following table shows the Vendor, Controller and Queue Depth. Note that this is based on what we (my readers and I) have witnessed in our labs and results my vary depending on the firmware and driver used. Make sure to check the VSAN HCL for the supported driver / firmware version, note that not all controllers below are on the VSAN HCL, this is a “generic” list as I want it to serve multiple use cases.

Generally speaking it is recommended to use a disk controller with a queue depth > 256 when used for VSAN or “host local caching” solutions.

HPSmart Array P700m1200

Vendor Disk Controller Queue Depth
Adaptec RAID 2405 504
Dell (R610) SAS 6/iR 127
Dell PERC 6/i 925
Dell PERC H200 Integrated 600
Dell PERC H310 25
Dell (M710HD) PERC H200 Embedded 499
Dell (M910) PERC H700 Modular 975
Dell PERC H700 Integrated 975
Dell (M620) PERC H710 Mini 975
Dell (T620) PERC H710 Adapter 975
Dell (T620) PERC H710p 975
Dell PERC H810 975
HP Smart Array P220i 1020
HP Smart Array P400i 128
HP Smart Array P410i 1020
HP Smart Array P420i 1020
IBM ServeRAID-M5015 965
Intel C602 AHCI (Patsburg) 31 (per port)
Intel C602 SCU (Patsburg) 256
Intel RMS25KB040 600
LSI 2004 25
LSI 2008 25
LSI 2108 600
LSI 2208 600
LSI 2308 600
LSI 3008 600
LSI 9300-8i 600

Startup News Flash part 17

Number 17 already… A short one, I expect more news next week when we have “Storage Field Day”, hence I figured I would release this one already. Make sure to watch the live feed if you are interested in getting the details on new releases from companies like Diablo, SanDisk, PernixData etc.

Last week Tintri announced support for the Red Hat Enterprise Virtualization platform. Kind of surprising to see them selecting a specific linux vendor to be honest, but then again it probably also is the more popular option for people who want full support etc. What is nice in my opinion is that Tintri offers the exact same “VM Aware” experience for both platforms. Although I don’t see too many customers using both VMware and RHEV in production, it is nice to have the option.

CloudVolumes, no not a storage company, announced support for View 6.0. CloudVolumes developed a solution which helps you manage applications. They provude a central management solution, and the option to distribute and elimate the need for streaming / packaging. I have looked at it briefly and it is an interesting approach they take. I like how they solved the “layering” problem by isolating the app in its own disk container. It does make me wonder how this scales when you have dozens of apps per desktop, never the less an interesting approach worth looking in to.

FUD it!

In the last couple of weeks something stood out to me when it comes to the world of storage and virtualisation and that is animosity. What struck me personally is how aggressive some storage vendors have responded to Virtual SAN, and Server Side Storage in general. I can understand it in a way as Virtual SAN plays in the same field and they probably feel threatened and it makes them anxious. In some cases I even see vendors responding to VSAN who do not even play in the same space, I guess they are in need of attention. Not sure this is the way to go about to be honest, if I were considering a hyper(visor)-converged solution I wouldn’t like being called lazy because of it. Then again, I was always taught that lazy administrators are the best administrators in the world as they plan accordingly and pro-actively take action. This allows them to lean back while everyone else is running around chasing problems, so maybe it was a compliment.

Personally I am perfectly fine with competition, and I don’t mind being challenged. Whether that includes FUD or just cold hard facts is even besides the point, although I prefer to play it fair. It is a free world, and if you feel you need to say something about someone else product you are free to do so. However you may want to think about the impression you leave behind. In a way it is insulting to our customers. With our customers including your customers.

For the majority of my professional career I have been a customer, and personally I can’t think of anything more insulting than a vendor spoon feeding why their competitor is not what you are looking for. It is insulting as it insinuates that you are not smart enough to do your own research and tear it down as you desire, not smart enough to know what you really need, not smart enough to make the decision by yourself.

Personally when this happened in the past, I would simply ask them to skip the mud slinging and go to the part where they explain their value add. And in many cases, I would end up just ignoring the whole pitch… cause if you feel it is more important to “educate” me on what someone else does over what you do… then they probably do something very well and I should be looking at them instead.

So lets respect our customers… let them be the lazy admin when they want, let them decide what is best for them… and not what is best for you.

PS: I love the products that our competitors are working on, and I have a lot of respect how they paved the way of the future.

Updating LSI firmware through the ESXi commandline

I received an email this week from one of my readers / followers on twitter who had gone through the effort of upgrading his LSI controller firmware. He shared the procedure with me as unfortunately it wasn’t well documented. I hope this will help others in the future, I know it will help me as I was about to look at the exact same for my VSAN environment, thanks for sharing this Tom!

– copy / paste from Tom’s document –

We do quite a bit of virtualization and storage validation and performance testing in the Taneja Group Labs ( Recently, we were performing some tests with VMware’s VSAN and due to some performance issues we were having with the AHCI controllers on our servers we needed to revise our environment to add some LSI SAS 2308 controllers and attach our SSD and HDDs to the LSI card. However our new LSI SAS controllers didn’t come with the firmware mandated by the VSAN HCL (they had v14 and the HCL specifies v18) and didn’t recognize the attached drives.  So we set about updating LSI 2308 firmware. Updating the LSI firmware is a simple process and can be accomplished from an ESXi 5.5 U1 server but isn’t very well documented. After updating the firmware and rebooting the system the drives were recognized and could be used by VSAN. Below are the steps I took to update my LSI controllers from v14 to v18. [Read more...]


I noticed this new SuperMicro VSAN Ready Node being published last week. The configuration is potentially a nice solution for ROBO deployments, primarily due to the cost of the system.

When I did the math it came in around $ 3800,-. This is the configuration:

  • SuperMicro SuperServer 1018D-73MTF
  • 1 x Intel E3-1270 V3 3.5GHz- Quadcore
  • 32GB Memory
  • 5 x 1TB 7200 RPM NL-SAS HDD
  • 1 x 200GB Intel S3700 SSD
  • LSI 2308 Disk controller
  • 4 x 1GbE NIC port

It is a nice configuration that will allow for roughly fifteen 1 vCPU Virtual Machines with 3GB of memory and 60GB disk capacity per host. Personally I would use a different CPU and some more memory probably as that gives you a bit more headroom, especially during maintenance. The cost from a software point of view is socket based so you can increase memory and change the type of CPU with relative low cost impact. The SuperMicro server listed however is limited to the E3 CPU family and to 32GB but there are alternatives out there. (For instance the Dell R320 or maybe even the R210 etc)

From a software point of view the cost of this configuration is limited to 3 x VSAN license and 3 x vSphere. As VSAN even works with Essentials Plus and Standard you could leverage that to keep the cost down, but keep in mind that you won’t have DRS if you drop down to Standard or lower. Still sounds like a nice ROBO package to me, especially when you have many sites this could be a great way to create a standardized packaged solution.

Startup News Flash part 16

Number 16 of the Startup News Flash, here we go:

Nakivo just announced the beta program for 4.0 of their backup/replication solution. It adds some new features like: recovery of Exchange objects directly from compressed and deduplicated VM backups, Exchange logs truncation, and automated backup verification. If you are interested in testing it, make sure to sign up here. I haven’t tried it, but they seem to be a strong upcoming player in the backup and DR space for SMB.

SanDisk announced a new range of SATA SSDs called “cloudspeed”. They released 4 different models with various endurance levels and workload targets, of course ranging in sizes from 100GB up to 960GB depending on the endurance level selected. Endurance level ranges from 1 up to 10 full drive writes per day. (Just as an FYI, for VSAN we recommend 5 full drive writes per day as a minimum) Performance numbers range between 15k to 20k write IOps and 75 to 88K read IOps. More details can be found in the spec sheet here. What interest me most is the FlashGuard Technology that is included, interesting how SanDisk is capable of understanding wear patterns and workloads to a certain extend and place data in a specific way to prolong the life of your flash device.

CloudPhysics announced the availability of their Storage Analytics card. I gave it a try last week and was impressed. I was planning on doing a write up on their new offering but as various bloggers already covered it I felt there was no point in repeating what they said. I think it makes a lot more sense to just try it out, I am sure you will like it as it will show you valuable info like “performance” and the impact of “thin disks” vs “thick disks”. Sign up here for a 30day free trial!