Are you performing an agent backup or VM backup?

you mentioned linux VM on esxi host

We want to perform an agent backup because of postrgres backup. The linux vm resides on an esxi host wich is licensed with a socket-license. Currently we do no vm backup for this vm.

If you're using socket licenses and the ESXi host is already covered by such a license, then the agent doesn't need to be separately licensed (in fact it's mandatory to use a Socket license if you backup VMs with agents in that case).

I don't know any limitations and for some cases it's even recommended to go with agents; for example with mySQL or PostgreSQL. I would just do a restore test afterwards and check if the VM and it's disk come up without any problems. This is the main issue I often see, that after a restore both the OS and bootloader need to be touched because of new disk IDs.

We have a statement that it is not possible to install an agent on a VM running on a socket licensed host. For this reason I wanted to ask for any known cases that confirm this.

No that's not a problem as long as the host is licensed. It's just not possible to license a VM agent with a regular license in that case.

     Sockets will be used to protect VMs on VMware and Hyper-V hosts     Instances will cover Agents, Plug-Ins, AHV VMs, NAS excluding VMware and Hyper-V VMs.

https://www.veeam.com/licensing-policy.html?ad=faq

For VMs there is no restriction for the agents with socket based licenses. At least I am not aware of… I have several Enterprise plugins and agents in use on a socket licensed ESXi Cluster, no problem.

It is another thing if you want to use an agent on a hardware server, then an instance is used. The socket based licenses have 6 free instances included. So, you can use 6 server agents - or 18 workstation agents.

Hold up…..so are we saying that all VM’s on a licensed socket is covered for agents?  If so, I learned something today.  I knew about the “up to” 6 free agent licenses with perpetual licensing, but wasn’t aware of all VM’s on a licensed socket being covered for agents.

@JMeixner @regnor 

I believe that’s assuming that’s if you have 6 sockets licensed.  If you only have 4 sockets licensed, then it’s up to 4 free instances, correct?

No, I have in one cluster 10 Sockets licensed and in another 26 Sockets, every time 6 instances only. Seems to be a standard value.
In most environments I have VUL or VCSP hosting licenses, so I have no problem with this because they are completely instance based.

@JMeixner

1 free instance per socket, maximum 6 instances per license.

If you only have 4 sockets licensed, then it’s up to 4 free instances, correct?

@dloseke correct :)

Aha, ok, 6 is maximum. Too small for my clusters, I have the maximum with each cluster

Most of my customers are in the SMB space, so many only have 2-3 hosts in a cluster and use VMware Essentials kits and Veeam Backup Essentials in most cases, so there is a 6 socket max there.  Most are licensed perpetual but we’re converting some, obviously selling VUL’s new, etc.  We do have two clients on VCSP but rental licensing is more of a one-off for us….used for those few select folks that don’t want to buy or only needed a couple VM’s protected (VBE packs reduced to 5 workloads has reduced that need even more), or for us to use in a pinch when we need a solution right away and the client hasn’t purchased yet.

This behavior changed with v10 or v11 I think. Before that you would have had to license an agent if it's used in a virtual machine. The disadvantage on the other hand is, that you would have to license a whole ESXi host with socket licensing even if there's only a single VM which you want to backup via agent.

Okay, fair enough.  I came into Veeam 5 years ago with 9.5 U4 but didn’t spend a ton of time with it and got a lot more involved during the release of v10.