Largest Stack?
-
Hello all,
Question for anyone who uses XCP-NG:
Whats the most VMs you have running?
We have a 3 server pool of XCP-NG managed by XOA. Migrated from VMware due to the Broadcom stuff going on. Everything is stable. Running 22 VMs at the moment, about to add 32 more.
-
@Schmarvin It depends on memory/cpu/IO usage. Don't over subscribe memory and make sure there's enough CPU/cores to deal with the load. Then add one or two servers (N+2) so you have room for failures and upgrades. You want room for a host server to fail and still have enough space to migrate VMs so you can do an update.
There's not a fixed number of VMs per server. You might run one VM on one host server (eg. SQL server) and 20 VMs on another host server.
I have a pool of 5 host servers with about 60 active VMs. Some hosts run 20 or more VMs while others run 5 or so. It depends on the resources the VMs need. With new hardware (more CPU power and memory per host) could shrink the pool size.
-
@Andrew Yea, I know it depends on all that. I'm just curious on the most crazy environments. We don't have that many VMs, I don't think. But I'm curious what others have, no necessarily what the hardware running is...just the number of Virtual Machines in the Pool and how many servers run those many VMs.
-
@Schmarvin I have about 170 VMs show up in my main XO... about 70 are on one host server for backup/replication. I can start them all on the single machine but it would be short memory and CPU resources so I would have to cut back on resource allocation. It's normally about 50 active VMs on 3 active host servers due to resource limitations (that's why there's hosts 5 in the pool).
On one home server I have over 20 VMs on a little NUC server but only half running at the same time (only 64G memory).
-
@Andrew That's awesome. I'm just impressed. Moving from VMware/Vsphere, not ESXI, to XCP-NG w/ XOA, everything just works and is lightweight. The issues with VMware is the resources needed. Just the base system requires 4-8GB of RAM, each add-on, such as vsphere is an additional 6-8GB of RAM. And yes, the UI is great, but sometimes, it sticks and doesn't work.
-
We have users and customers with 10k VMs total at multiple datacenters with thousand of physical hosts.
Regarding the density, it really depends on your VM usage, so there's no universal rule, but with modern hardware, you can have really a LOT of VMs on a single machine.
-
@olivierlambert I know it is all based on physical hosts and hardware. I just like hearing stories of how massive these networks are on XCP-NG.
-
@Schmarvin said in Largest Stack?:
@olivierlambert I know it is all based on physical hosts and hardware. I just like hearing stories of how massive these networks are on XCP-NG.
What you mean to say is that there needs to be some white-papers on how XCP-ng and XO have worked for some large enterprise customers.
-
@DustinB No, not really. I just like hearing peoples opinions from a personal perspective and not corporate lingo.
-
Now we have 76 VMs running on a 3 host pool. Each server has 320 GB of RAM.
Our scenario doesn't need big CPU resources so everything works fine.
