This is a common misunderstanding regarding SDC configuration, made more unclear due to restricted SDC mode requiring the manual addition of an SDC via SCLI.
Without that mode enabled, SDCs just need a GUID and the MDM IPs to register themselves.
Restricted-mode SDCs do not need all IPs added to the MDM's configuration, only one. In fact, you could use the management network IP of the SDC. The SDC then pulls the MDM and SDS clusters' layout and connects to the SDS IPs that it can reach.
In your case, if you can vmkping -I vmkX 10.209.46.1 (and 2,3,4, etc) as well as vmkping -I vmkY 10.209.47.1 (and 2,3,4, etc), then you have connectivity to the SDSes on both subnets.
The SDC will use all available subnets to reach the SDSes. If you have 3 subnets for data on the SDSes and only 2 configured on the SDCs, then you will connect via the two available subnets. If you add the 3rd subnet to the SDCs, they will then also connect to the SDSes on the third subnet. (The exception to this being SDS IP role configuration, which dedicates an IP/subnet to either SDC-only traffic, or SDS-only traffic.)
Best practice is to maintain a 1:1 ratio of NICs/vSwitches to subnets.
This makes a lot more sense. I have no real way to know if it is using those networks though. I'll get this all setup and see how it performs. I really appreciate the detailed answer, Rush!
daverush
51 Posts
0
February 13th, 2016 14:00
Alex,
This is a common misunderstanding regarding SDC configuration, made more unclear due to restricted SDC mode requiring the manual addition of an SDC via SCLI.
Without that mode enabled, SDCs just need a GUID and the MDM IPs to register themselves.
Restricted-mode SDCs do not need all IPs added to the MDM's configuration, only one. In fact, you could use the management network IP of the SDC. The SDC then pulls the MDM and SDS clusters' layout and connects to the SDS IPs that it can reach.
In your case, if you can vmkping -I vmkX 10.209.46.1 (and 2,3,4, etc) as well as vmkping -I vmkY 10.209.47.1 (and 2,3,4, etc), then you have connectivity to the SDSes on both subnets.
The SDC will use all available subnets to reach the SDSes. If you have 3 subnets for data on the SDSes and only 2 configured on the SDCs, then you will connect via the two available subnets. If you add the 3rd subnet to the SDCs, they will then also connect to the SDSes on the third subnet. (The exception to this being SDS IP role configuration, which dedicates an IP/subnet to either SDC-only traffic, or SDS-only traffic.)
Best practice is to maintain a 1:1 ratio of NICs/vSwitches to subnets.
daverush
51 Posts
0
February 13th, 2016 14:00
Also,
https://support.emc.com/kb/466097 details ESX SDC config and troubleshooting, minus the restricted SDC mode.
Alex10
2 Posts
1
February 19th, 2016 12:00
This makes a lot more sense. I have no real way to know if it is using those networks though. I'll get this all setup and see how it performs. I really appreciate the detailed answer, Rush!