iSER on ONTAP

[amayacitta]

Hey, does anyone know if iSER (iSCSI Extensions for RDMA) will ever be implemented on ONTAP? I know this is avialable on E-Series, it also seems there is more of a push in the ONTAP space for NVMe, however this would really benefit existing customers that are not on NVMe and want to push their performance. The numbers quoted from VMware look pretty impressive.

We do a fair bit of FlexPod and having this for AFF220 for example would be awesome. It works with Cisco VIC 1340 for example on the host end.

https://blogs.vmware.com/performance/2018/08/vsphere-with-iser-iscsi-extensions-rdma.html

https://storagehub.vmware.com/t/vsphere-6-7-core-storage-1/iser-iscsi-extensions-for-rdma-support-in-vsphere/

[nboggs]

Have you opened a case for this?  I searched The onTap documentation and also the bert site for any mention of iSER.  Could only find information about it in e-series.  You could see if a a request for enhancement can be raised through a case.

[amayacitta]

Was kinda hoping a product manager would read the forum. I'll open a P4 case and see what they say, will refer them to this forum post.

Cheers.

[nboggs]

Ok well they still might :).  Anyways let us know what the eventual answer is.

[AlexDawson]

We'd love to hear more details about how you would use this with A220 FlexPods - it sounds like you might have a few?

If you can open a case asking how to enable iSER for iSCSI on ONTAP, along with details of the number of systems you have right now and how many you would be purchasing over the next 18 months, and then post the case ID here, we will make sure it gets to our product management team for review. I had a bit of a look through our cases and can't see yours.

Product design, feature selection, testing and deployment lifecycles tend towards longer term questions, so the sooner the better. We don't aim for feature parity between E-Series and ONTAP, so there will always be a few differentiators.

Thanks!

[amayacitta]

The case ID is 2008298314.

RDMA is part of the standard feature set on the UCS adapter policies and QoS System Classes. We can configure on Nexus, so the only missing part is storage. There are Cisco design guides for RDMA with RoCEv2 for other protocols, certain VIC models support it and you can also put a Mellanox card in a C-Series server if you have one.

The AFF220 supports RDMA and iWARP for MCC IP. We would just need to expose that feature set more broadly for normal network connectivity and add RoCE support. As I understand it RoCE is a leaner choice that iWARP as it doesnt sit inside TCP, Mellenox claim it's much faster than iWARP here.

Here is a pic of where the setting is in UCS manager, it supports v1 and v2.

[amayacitta]

Sorry to dig up an old thread, but now with the arrival of A250 etc and X1152 adapter cards, is RoCE (v1 or v2) possible with ONTAP?  The only reference to RDMA outside of Metro clusters is the below link which suggests you can leverage RMDA transport ports for NVMe-Of without FC which has been supported since ONTAP 9.4.

https://docs.netapp.com/ontap-9/topic/com.netapp.doc.onc-sm-help-960/GUID-D6E15909-0910-4FA9-B1A5-D13E1E57D514.html

I have one of these to deploy and the switch + host end has full support for RDMA, so i'd like to try and leverage it for NVMe or iSER if possible. Thing is without documentation, i'm not sure its possible to enable the RDMA feature present on the X1152 on the NetApp end.

[amayacitta · Accepted solution]

FYI - A contact within NetApp told me RDMA transport is planned for a future release, possibly due this year but no commitments. So we need to wait 🙂 a FPVR has been raised for our customer solution.