At VMworld various people asked me why VMware did not support the use of Storage DRS and Storage IO Control in a VPLEX Metro environment. This was something new to me and when someone pointed me to a KB article I started digging.
When discussing it with the various teams the following is what we concluded for EMC VPLEX, this is what I drafted up. I have requested the KB to be updated in a more generic fashion (text all the way down below) so that the support statement will apply for all vMSC configurations. Hopefully will be published soon. The EMC specific statement, which I provided to the EMC VPLEX team, will look roughly as follows:
EMC VPLEX supports three different configurations, namely VPLEX Local, VPLEX Metro and VPLEX Geo. This KB article describes the supported configurations for VPLEX Local and VPLEX Metro with regards to Storage DRS (SDRS) and Storage I/O Control (SIOC). VMware supports Storage DRS and Storage IO Control on EMC VPLEX in each of the two configurations with the restrictions described below.
VPLEX Local:
In a VPLEX Local configuration VPLEX volumes are contained within site/location. In this configuration the following restrictions apply:
– Storage IO Control is supported
– Storage DRS is supported
– A Datastore Cluster should only be formed out of similar volumes
– It is recommended to run Storage DRS in “Manual Mode” to control the point in time migrations occurVPLEX Metro:
In a VPLEX Metro configuration VPLEX volumes are distributed across locations/sites. In this configuration the following restrictions apply:
– Storage IO Control is not supported
– Storage DRS is only supported when “IO Metric” is disabled
– It is recommended to run Storage DRS in “Manual Mode” to control the point in time migrations occur
– Each location/site should have a Datastore Cluster formed only out of dvols (Distributed VPLEX volumes) which are part of the same consistency groups, and only with site bias to that particular location / site!
– Example: Site A will have Datastore Cluster A which contains all dvols with bias to Site A.
The more generic support statement will roughly look like this:
This KB article describes the supported configurations for vSphere Metro Storage Cluster (vMSC) environments with regards to Storage DRS (SDRS) and Storage I/O Control (SIOC). VMware supports Storage DRS and Storage IO Control with the restrictions described below.
In a vMSC configuration volumes are distributed across locations/sites. In both uniform and non-uniform configurations the following restrictions apply:
– Storage IO Control is not supported
– Storage DRS is only supported when “IO Metric” is disabled
– It is recommended to run Storage DRS in “Manual Mode” to control the point in time migrations occur
– Each location/site should have a Datastore Cluster formed only out of stretched datastore and only with site bias to that particular location / site
– Example: Site A will have Datastore Cluster A which contains all stretched datastores with bias to Site A.
Hopefully this will help the folks implementing vMSC today to make the decision around the usage of SDRS. KB team has informed me they are working on the update and as soon as it has been published I will update this article.
** KB Article has been updated: http://kb.vmware.com/kb/2042596 **