Recently we got some storage problems with a couple of ESXi hosts and one of the recommendations of the VMware support was to update the async drivers. I think that there isn’t much awareness about those drivers as it actually should be, that’s why I wrote this short post.
Async drivers are developed by partners like QLogic and certified by VMware to optimally support their hardware. A good example is the pretty common Fibre Channel HBA QLE2562.
A certain version of those drivers will be shipped with the VMware ESXi image or the corresponding OEM images. As you probably can imagine that those drivers updated more often than the ESXi images. An example of which QLogic drivers are included in the VMware ESXi images can be found here: Default QLogic HBA driver/firmware versions for ESXi
OEMs like Dell will probably include more recent drivers for their hardware when they release an updated version of the image like the following:
In case of the Dell images it’s recommended to take a look at the “Important Information” section on the Dell download site to check which drivers are really included:
Qlogic HBA Drivers & its versions(Available at vmware.com) ==================================================
qla2xxx – 922.214.171.124-1vmw
qla4xxx – 6126.96.36.199
qlcnic – 5.1.157
qlge – v2.00.00.57
In addition to that the drivers are also available in the VMware patch depot to be downloaded manually. These could be used to create a custom ESXi image using the “Image Builder CLI” or for a manual installation via CLI:
esxcli softwarev install -d offline-bundle.zip
The offline bundles can be found in the my.vmware.com download portal within the „Drivers & Tools” section, listed under “Driver CDs”. Those downloads also include the corresponding release notes.
This “mean” thing is that those drivers won’t be shipped via the Update Manager. Of course you could use the Update Manager to install them, but it will require to download them manually and to import them into the patch repository. Depending on the number of HBA/NICs this can be a bit cumbersome but it will be the only way to have them up to date other than updating the ESXi using a new image.
The KB article 2030818 (supported driver firmware versions for I/O devices) offers a link collection to the corresponding vendors like QLogic and their own VMware compatibility matrix. This matrix lists the latest driver version as well as the recommend firmware which should be applied accordingly.
To check which version is currently installed on your host, you could also use the Update Manager or the following CLI command:
To determine which driver is really actily used by the HBA can be verified via
But why is it actually important?
As with all pieces of software also drivers can contain bugs that need to be fixed or they get new feature, improved performance or support for new hardware devices. So if an outdated driver contains a bug which may affect the failover behavior of an ESXi host, this can have a significant impact on your environment!
By the way ESXi 5.5 introduced a new driver architecture called Native Device Driver. Currently a ESXi can run in hybrid mode to support the new and the “legacy” driver which is why the HCL currently shows two different types of drivers.