Upgrade VDS to 6.5.0 - impact

[andvm]

Hi,

VCSA 7.0 requires all VDS to be on version 6.5.0 (minimum) or 6.7.0

Currently on 6.0.0 on a few of them so will need to upgrade to 6.5.0

What is not entirely clear is depending on which vSphere version you select (top right) a brief downtime is experienced:

Upgrade a vSphere Distributed Switch to a Later Version

I want to know if the downtime is linked to the vSphere version the Host/s are running for example 6.7.0 or if linked to the DVS version being upgraded to for example 6.6.0

vSphere versions will be a mix of 6.7.0 and 6.5.0 and DVS will be upgraded to 6.5.0 - is downtime to be expected? other considerations I should make (backup DVS config)?

Thanks

[harry89]

I would suggest you to go through the below articles thoroughly , as there are few scenario which need to be understood prior .

More criticality comes into picture if you have NSX configured and using PVLANs

VMware Knowledge Base

VMware Knowledge Base

[andvm]

the first link is for an upgrade to 6.6.0 which I will not do primarily because some hosts are still on 6.5 but also because it clearly states that some downtime is expected.

the second link is for vMotions where different VDS exist, I plan to upgrade to DVS 6.5.0 and make sure that any DVS (including DVS used for vSAN) in the respective DC will be on 6.5.0

No NSX or PVLANs

Still need to confirm if a DVS upgrade from 6.0.0 to 6.5.0 involves any downtime or not (irrespective if ESXi is 6.5 or 6.7)

[harry89]

I tried now in my lab .

• Created Test DVS on 6.0 version
• Added host  which is on 6.7
• Added and migrated host networking (vmk and virtual machine to DVS)
• Continuous ping to esxi management and virtual machine
• Upgrade the dvs to 6.5
• No packet drops neither on vmk nor on virtual machine

[andvm]

That is promising thank you

Did the DVS upgrade take a few seconds to upgrade or was it longer?

[berndweyand]

upgrading a dv-switch to a higher version is only unlocking new features - no impact to current traffic

[harry89]

It took only few seconds in my case

[andvm]

I would still act on the side of caution especially if VMware Docs says that a brief downtime is to be expected Upgrade a vSphere Distributed Switch to a Later Version

[andvm]

Should the upgrade fail, I should be a able to restore the DVS config from backup

However I notice the following:

"You can use a saved configuration file to restore policies and hosts associations on the distributed switch. You cannot restore the connection of physical NICs to uplink ports or ports of link aggregation groups."

Backing Up and Restoring a vSphere Distributed Switch Configuration

Does this mean that if I had to restore the config I would end up with the DVS with all portgroups/config but without any uplinks bound to it?

Thanks

[harry89]

• Brief downtime or interruption is mostly for nsx and LAG use case .
• That happens because when NSX owns DVS , it adds multiple dvfilter and update of them can cause brief interruption
• But with core networking this is highly unlikely
• Anyways you can do it in off business hours .

Cheers!

[andvm]

good to know, yes LAG is used on almost all DVS.

there is no such (easy) off business hrs - would be great if so

Let me know if you have any feedback on the restore questions in relation to uplinks

Thanks

[harry89 · Accepted solution]

Restoring the configuration will restore the settings of the dv port groups and dv switch itself.

Some testing in lab to provide you more clear understanding

• Created a DVS switch DVS-2
• Add one host uplink vmnic1 to the host .
• Took the backup of DVS
• Changed the vlan on dvs port group to 12 (any random) from none
• Changed the MTU on switch to 2000 (earlier 1500).
• Right click switch restore the configuration
• Restore completed
• Up-link(vmnic1) still part of the dvs . Host is still added
• MTU on DVS switch reset to 1500
• VLAN on  dvportgroup reset to none.

So it basically just restore the settings , configuration  of dvswitch and port groups , which is there on XML (back up file).

No impact on the up links

Cheers !!

[andvm]

Appreciated Harry, will check if there is an HOL available that lets you replicate such scenario (Create/Upgrade/Restore and test VDS)

[sc2317]

Hi,

I think restoring does not reverts the upgraded version to the old one ? As per VMware, you can only revert the version by using Import configuration which will create new DVS. I think VMware has not explained it in detailed. Also, if earlier versions if upgrade fails then it will automatically reverts. I am not sure if that's changed.

[PcChip]

how did this go?  We're using LACP like you and are trying to get an idea of downtime

6.5 hosts going to dvswitch 6.5 and also enabling eLACP, so that we can migrate to vCenter 6.7