Highlighted
Enthusiast
Enthusiast

Using link mode over long distance?

Hello,

We are building a cluster of 6 vhosts. For management our parent company has offered use of their vCentre Server cluster as they have some spare licences. However they are in another country, but we do we have a private connection to them.

I have 3 options I'm considering:

a) We add our 6 hosts to one of their existing vCentre Server's and use them for monitoring.

b) We setup another vCentre Server local to our vhosts and use link mode to the main vCenter Server cluster.

c) We see if there is someway to transfer the spare licences to a cVentre Server at my office and make it completely stand alone.

To be honest (c) is my preferred option, but I'm not sure how possible that is with our licencing agreement.

Of (a) and (b) - has ayone had experience with this kind of setup? My main worries are what happens if the link goes down? With option (a) I guess we lose all management. With (b) what happens if our on site server contact the main cluster?

Also (very roughlty) is there a lot of data transfer down the link between linked vCentre servers? We would have 6 hosts and say 50VM's

Thanks for any info.

Nick

0 Kudos
3 Replies
Highlighted
Virtuoso
Virtuoso

mrnick1234567 wrote:

a) We add our 6 hosts to one of their existing vCentre Server's and use them for monitoring.

b) We setup another vCentre Server local to our vhosts and use link mode to the main vCenter Server cluster.

Of (a) and (b) - has ayone had experience with this kind of setup? My main worries are what happens if the link goes down? With option (a) I guess we lose all management. With (b) what happens if our on site server contact the main cluster?

I'm running a setup similar to A currently, but with a pair of GigaMANs between the datacenters. If the link goes down, you lose the ability to easily manage your infrastructure (especially vMotion) but can still connect to individual hosts, which depending on your site is either mission critical or an annoyance.

I've set up B in a lab environment. It's a very simple process that requires little administrative effort. You essentially just choose linked mode when installing the 2nd vCenter server. Domain trust is a factor, as well as roles.

This link contains some info: http://pubs.vmware.com/vsp40_e/wwhelp/wwhimpl/js/html/wwhelp.htm#context=admin&file=c_using_vcenter_...

c) We see if there is someway to transfer the spare licences to a cVentre Server at my office and make it completely stand alone.

You would definitely need an additional vCenter license ... I suppose you could install the vSphere license key on this host, but I'm not entirely sure if that's legal. There is no "big brother" for licenses that I'm aware of.

Also (very roughlty) is there a lot of data transfer down the link between linked vCentre servers? We would have 6 hosts and say 50VM's

I wouldn't be concerned with traffic for that amount of VMs. We're talking under 100kbps.

VCDX #104 (DCV, NV) ஃ WahlNetwork.com ஃ @ChrisWahl ஃ Author, Networking for VMware Administrators
Highlighted
Enthusiast
Enthusiast

HI Chris,

Thanks, this is really helpful. Can I ask - for your test setup for the (b) scenario, have you tried pulling the link? I'm interested to know if you lose management straight away, or if it continues to function stand alone (say until it next decides to poll for a licence).

Nick

0 Kudos
Highlighted
Virtuoso
Virtuoso

Yes, I disabled network access to the 2nd "remote" vCenter server. The inventory for that vCenter server clears out of the vSphere Client, and a red error box appears in the lower right corner stating that it could not reach the server.

I did not lose the ability to manage the objects in the "local" vCenter server, but I had installed licenses on that particular server. I'm not sure what would happen if the licenses were on the other server.

VCDX #104 (DCV, NV) ஃ WahlNetwork.com ஃ @ChrisWahl ஃ Author, Networking for VMware Administrators