Change ESXi to Synology iSCSI connection

I’m not sure if this should be under this category or networking :grinning:

Anyway, I have my ESXi 7.0 server connected to my Synology RS1221+ using iSCSI for my VMs (homelab but I like to keep it running well). I am currently using a 1GbE connection (it works but isn’t the fastest :wink:) on a separate subnet/VLAN that goes through my UniFi SW24Gen2 (e.g., 192.168.21.0/24 without a gateway/default route and using a dedicated VLAN - 21 in this case).

I have just added a 10GbE Synology dual port card to my NAS. As I do not have a 10GbE switch, this will be a direction connection (e.g., NAS to ESXi host). I am waiting on a second DAC cable to add redundancy between ESXi and the NAS. Here are my questions:

  1. Should I remove the 1GbE iSCSI connect on the ESXi side before adding the 10GbE connection? I don’t think that you can have mixed speeds for iSCSI in this case.
  2. Related to the above, if I leave both in place should I use different subnets?
  3. Should I wait until the second DAC cable arrives before making the change? It is more work/risk to add the redundant network connection?

Any other suggestions (or warnings!) are welcome!

Cheers and Thanks!

If they are direct connecting you need to static set the IP addresses interfaces and make sure there is no overlap between the existing subnets. I am not sure if iSCSI mutlipath works well with different speeds, might get some unexpected results.

To close this off, it seems that with mixed speeds ESXi will select the first network that was set up.