Nexenta: Configuring iSCSI Multipath Target with multiple network cards
This is a short post about how to configure iSCSI multipathing using Nexenta. I let it is neccessary to document it since the documentation is rather spare about it.
In my lab setup i had a machine with two physically separated interfaces:
- e1000g0: 192.168.1.5/24 and
- e1000g1: 192.168.10.1/24
As you can see both interfaces are on different subnets. Note that it is a very good idea (i´d call it: “required”) to use a separate subnet for each interface. It will save you a lot of trouble and problems!
Note: If you modify and existing installation you only need to execute Step #2 and Step #3. Everything else should already be there.
Step #1 : Create an iSCSI target
This step is only required if you do not yet have one. If you already have one – skip this step.
Enter a desired target name into the name field or leave it blank to automatically create one:
The created target looks like this:
Step #2: Create Target Portal Groups
You need to create one Target Portal Group for each interface you want to use for iSCSI. In our case we will create two Portal Groups because we want to use two interfaces:
The result looks like this:
Step #3: Reconfigure iSCSI Target
In the next step we add our created target portal groups to the iSCSI target (created in Step #1):
Bascially were done here. Step 4 – 8 shows how to create a LUN and map these LUN to target and initiator.
Step #4: Create Target Group
If you do not already have a target group create one and add your iSCSI target. If you already have a target group skip this step.
Step #5: Create a ZVOL
A ZVOL is the LUN which will be visible on the initiator:
Step #6: Create Remote Initiator
To map a LUN (or ZVOL) to the appropriate clients you need to create a Initiator Group. These group consists of remote initiator names. The initiator name can either be found on the client e.g. Linux stores the initiatorname in /etc/iscsi/initiatorname.iscsi) or – if the client is already connected to the target – it will be display in Step 7.
If you want or need to create the remote initator manually you can do this under ‘Remote Initiator’:
This step finally creates the remore initiator group and assigns a name to them:
Step #8: Map Target Group, Initiator Group and ZVOL
The last step finally maps the ZVOL (= the LUN to be exported), the initiator group (= the client(s) you want to export the LUn to) and the target group (the protocol you want to use to export the LUN):