With the introduction of our Active-Active Synchronous Replication (called ActiveCluster) I have been getting more and more questions around multiple-subnet iSCSI access. Some customers have their two arrays in different datacenters, and also different subnets (no stretched layer 2).
With ActiveCluster, a volume exists on both arrays, so essentially the iSCSI targets on the 2nd array just look like additional paths to that volume–as far as the host knows it is not a two arrays, it just has more paths.
Consequently, this discussion is the same as if you happen to have a single array using more than one subnet for its iSCSI targets or if you are using active-active across two arrays.
Though there are some different considerations which I will talk about later.
First off, should you use more than one subnet? Well keeping things simple is good, and for a single FlashArray I would probably do that. Chris Wahl wrote a great post on this awhile back that explains the ins and out of this well:
Continue reading ESXi iSCSI, Multiple Subnets, and Port Binding
Another how-to post on iSCSI. Essentially another “for the good of the order post” here. iSCSI is becoming increasingly common, so figured I would put a post together that covers the ins and outs of port binding with standard vSwitches.
For information on distributed switches (which I highly recommend using over standard vSwitches) check out this post here:
Setting up Software iSCSI Multipathing with Distributed vSwitches with the vSphere Web Client
So on to Standard vSwitches. Continue reading Setting up iSCSI Port Binding with Standard vSwitches in the vSphere Web Client
Sorry the title is a bit of a mouthful.
I have written some posts on iSCSI in the past, around setup:
Setting up iSCSI with VMware ESXi and the FlashArray
Configuring iSCSI CHAP in VMware with the FlashArray
Another look at ESXi iSCSI Multipathing (or a Lack Thereof)
These have been on various parts, but primarily the setup around standard vSwitches, which generally, in at least in larger environments, is not the norm. Distributed vSwitches are. I have seen a few posts on doing this with the old C# client, but not the vSphere Web Client. Reference those posts here:
So with the amount of questions I have received on it, it is probably worth putting pen to paper on it. Nothing profound here, basically a walkthrough.
This is of course assuming you are doing port binding. If you are not, then just the standard software iSCSI setup (as described in the above 1st post) is needed.
Continue reading Setting up Software iSCSI Multipathing with Distributed vSwitches with the vSphere Web Client
So we ran into a customer issue recently with VMware Site Recovery Manager that I have not seen before and have not found any on-point articles on, so I thought I’d share this one. Was an insidious one too, when troubleshooting this one I could not find the issue, eventually one of our rockstar escalation engineers at Pure (Jacob Hopkinson) figured it out after going through SRM debug logs line by line. Comes down to case sensitivity in iSCSI IQNs. I’ll explain…
Continue reading SRM Cannot Identify Replicated Datastores on iSCSI Devices
I jumped on a call the other day to talk about iSCSI setup for a new FlashArray and the main reason for the discussion had to do with co-existence of a pre-existing array from another vendor. They were following my blog post on iSCSI setup and things didn’t quite match up.
To setup multi-pathing (the recommended way) for Software iSCSI is to configure more than one vmkernel port that each have exactly one active host adapter (physical NIC). You then add those vmkernel ports to the iSCSI software adapter and the iSCSI adapter will then use those specific NICs for I/O transmission and load-balance across those ports.
Continue reading Another look at ESXi iSCSI Multipathing (or a Lack Thereof)
I recently posted the process of configuring iSCSI on ESXi with the Pure Storage FlashArray. One of the things I left out is (optional) CHAP security configuration. It is a pretty straight forward process but worth writing down to save anyone who wants to configure it a few document cross-reference checks.
Continue reading Configuring iSCSI CHAP in VMware with the FlashArray
I’ve been with Pure Storage for about ten months (time flies!) and a noticeable trend I’ve seen in the past six or so months is in the number of customers who are deciding to use iSCSI as their storage protocol of choice. This is increasingly common in greenfield environments where they don’t want to invest in a Fibre Channel infrastructure. I’ve helped quite a few set this up in VMware environments so I thought I would put a post together on configuring ESXi software iSCSI with the Pure Storage FlashArray (I have yet to see a hardware iSCSI setup).
Before I begin, I highly recommend reading the following two documents from VMware:
They are not long and provide very good insight into the how/what/why of iSCSI on VMware. Some of the images are a bit old, but the underlying concepts have not changed. Continue reading Setting up iSCSI with VMware ESXi and the FlashArray
I recently posted about adding capacity to a ScaleIO storage pool, so the next logical step is provisioning a new volume. In this post, I am going to cover the straight-forward act of creating a new volume from a storage pool, mapping it to a ScaleIO Data Client (SDC) and then presenting it to the VMware cluster.
The first step is to assure we have enough space to configure a new volume of the size we desire. GUI or CLI will suffice:
Continue reading Provisioning a new ScaleIO volume in a VMware environment