topic Smart Link functionality with multiple Uplink Sets in same Network Set in HPE Synergy

Smart Link functionality with multiple Uplink Sets in same Network Set

Shakedown1979 — Sat, 20 Mar 2021 19:13:17 GMT

Hi there,

Have a question around Smart Link functionality, and how this would react with a particular situation. I've had a good search around on here, and in the usual places but can't find a definitive answer.

I have a considerable number of Synergy CMs running ESXi, each host with a pair of NICs in a LAG on a vDS. The Connections in the OneView Server Profiles for these are a Network Set which is made up of Networks trunked from multiple Uplink Sets. Some of these Networks have Smart Link currently enabled.

I need to decommission the Ethernet fabric of one of the Uplink Sets, and as such all the uplink ports of that Network Set would show as down. As I understand Smart Link, this would cause the download ports to automatically disable. This would be bad news, as the other Uplinks Sets participating the Network Set are still very much active.

How would Synergy/OneView handle this situation? It is also the case that not all of the Networks in the Network Set are enabled for Smart Link.

Many thanks!

(Running 4.20.01.01-0385523, 40Gbps F8 f/w 1.4.0.1003, and SY480 CMs running ESXi6.5/6.7)

Re: Smart Link functionality with multiple Uplink Sets in same Network Set

Nikhil93 — Wed, 24 Mar 2021 03:35:08 GMT

Hi Shakedown1979,

Thank you for posting your query. As I see, you are looking for Smart Link functionality with multiple Uplink Sets in same Network Set.

This is to inform you that our engineers are looking into this and we will reply to you shortly.

Kindly await with us.
Regards,

R. Nikhil
I am an HPE Employee

Re: Smart Link functionality with multiple Uplink Sets in same Network Set

Mansoor1 — Wed, 24 Mar 2021 17:40:13 GMT

Smart Link enables the server software to detect and respond to a loss of network connectivity on the interconnect uplink ports. Smart Link causes the operating system to detect a failure and direct traffic to an alternative path. With Smart Link enabled, the Virtual Connect interconnects will drop the Ethernet link on all server connections associated with the network if all uplink ports within an uplink set lose their connection to the data center switches.
Smart Link can be helpful when using certain server network teaming (bonding) policies.
Smart Link is only required and effective in the non redundant A/B side configurations. It has no effect on high availability or redundant configuration where both ICMs are in the same logical interconnect and MLAG is in use.
If a server profile connection contains network sets with both Smart Link and non-Smart Link enabled networks, no Smart Link processing occurs. This means that the profile connection always remains linked, even if uplink connectivity is lost for the Smart Link enabled networks.
If a server profile connection contains network sets with only Smart Link enabled networks and if all the uplink connectivity is lost for the networks in the network set, the server profile connection becomes unlinked due to Smart Link. The warning message indicates the reason for loss of connectivity.
Smart Link is not supported on HPE Composable Rack configurations.
Smart Link is supported on all Virtual Connect Ethernet interconnects:
· HPE Virtual Connect SE 40Gb F8 Module for HPE Synergy
· HPE Virtual Connect SE 100Gb F32 Module for HPE Synergy

If the above information did not answer your question, we would request you to log a case with HPE with LE dump for accurate response after reviewing your current environment.

Hope this helps.

Re: Smart Link functionality with multiple Uplink Sets in same Network Set

Shakedown1979 — Thu, 25 Mar 2021 20:27:26 GMT

Thanks Mohammed,

that's a brilliantly detailed response, and answers my question completely.

Thanks for the answer!