Hello everybody, my name is Martín, from Spain (so sorry for my poor English). I've been administering xenserver since 2010, fortunatelley, not too hard, beucause it works like a charm the most of the time. After being stalled in xenserver 7.2 for years, I've finally convinced my boss to move to xcp-ng, so here I am, with a new pool of 5 Lenovo SN550 and a fresh install of XCP-NG. Initially, we are doing with xcp-ng center to smooth the transition, although I'm running a XOA VM for a long, curiously I can't register it, but it is another story that I'll post as soon as I find the correct section.

Thanks for all your effort on the project and selfless help.

@danp said in This server is a different version to the master:

5.601

You are rigth, the problem was there. I didn´t found any package related to the schema version, but are rigth, so I've look into this. Here a problem like mine, and the key to resolv it. As my host0 was not updated, it was working with schema version 5.601. just a xe-tools-restart was enough to update the schema version to 5.602 and now they match.

Thanks!

In other words, you must empty the host before add it to the primary pool, of course, you can migrate VM from one pool to another. And if your hw is not the same, but similar, you'll have an heterogeneous pool.

Everything clear.
Thanks.

@danp said in This server is a different version to the master:

5.601

You are rigth, the problem was there. I didn´t found any package related to the schema version, but are rigth, so I've look into this. Here a problem like mine, and the key to resolv it. As my host0 was not updated, it was working with schema version 5.601. just a xe-tools-restart was enough to update the schema version to 5.602 and now they match.

Thanks!

@danp Yes, I considered it, even tried a pool migration, but disks of 1TB take long hours to finally fail. What's more when I've migrate a machine, (and I've migrated several hundreds of them), time to time one of them gets bock and need a reboot, which is something I want to avoid, specially if I don't know when is going to finish, because i takes several hours (may finish at 3 a.m and no one there to check it's correct)

Hello everyone,
I have one standalone host in a pool (yes, a pool of one), let's name it host0. This was a 8.1 versión updated to 8.2 by "yum update" before any VM was running there.

Now, I have a new and identical host (host1) to add to this pool, but I can't add it to the pool because it says that version of master (host0) is different.
Host0 was updated to 8.2 and started running several VM on it, so is not possible to reboot it in order to be updated, but a yum update was done, I mean, it is waiting for a reboot to be 100% efective.
Host1 was install in the same way, firstly 8.1 and it is updated later to 8.2. This process lets host1 updated to last available versions, while host0 is not, because the reboot is not possible.

I've look into host0 version and downgrade host1 to the same version, but it continues mismatching version.

xe host-param-list uuid=7fa3f334-f878-4608-9cb5-0d2707706f86 |grep version
                     API-version-major ( RO): 2
                     API-version-minor ( RO): 16
                    API-version-vendor ( RO): XenSource
     API-version-vendor-implementation (MRO): 
                      software-version (MRO): product_version: 8.2.0; product_version_text: 8.2; product_version_text_short: 8.2; platform_name: XCP; platform_version: 3.2.0; product_brand: XCP-ng; build_number: release/stockholm/master/7; hostname: localhost; date: 2020-11-05; dbv: 0.0.1; xapi: 1.20; xen: 4.13.1-9.8.2.xcpng8; linux: 4.19.0+1; xencenter_min: 2.16; xencenter_max: 2.16; network_backend: openvswitch; db_schema: 5.601
    virtual-hardware-platform-versions (SRO): 0; 1; 2

xe host-param-list uuid=7e5f26d9-59d6-4674-ad7f-344e93c5ebb2 |grep version
                     API-version-major ( RO): 2
                     API-version-minor ( RO): 16
                    API-version-vendor ( RO): XenSource
     API-version-vendor-implementation (MRO): 
                      software-version (MRO): product_version: 8.2.0; product_version_text: 8.2; product_version_text_short: 8.2; platform_name: XCP; platform_version: 3.2.0; product_brand: XCP-ng; build_number: release/stockholm/master/7; hostname: localhost; date: 2021-05-20; dbv: 0.0.1; xapi: 1.20; xen: 4.13.1-9.8.2.xcpng8; linux: 4.19.0+1; xencenter_min: 2.16; xencenter_max: 2.16; network_backend: openvswitch; db_schema: 5.602
    virtual-hardware-platform-versions (SRO): 0; 1; 2

As you can see, according to host, they are running the same version, but something is missing. What I'm trying is add host1 to the pool ruled by host0, move every VM to host1 and reboot host0 to get it updated, repeating the process with host1.
Any idea about how to get a matching version working only on host1?
Thanks in advance

@olivierlambert It didn't work. So I had to reboot the host. Is the same under xcp-ng 8.2?

@olivierlambert Hi,
I'm using xenserver 7.2 (pending migratin to xcp-ng in this pool)
I had to reboot the host, and as espected, it worked, any way, I'd like to know it another option would had worked.

Hello everyone.
I had to restart my pool master toolstack, and no way to reconnect to it again from XCP-ng center.
I'm talking about a pool of 8 host running 7.2 xenserver.
After log into the host I realized the /var/log partition was full, so there is the problem. I take from granted that a host reboot should resolve the problem, but as always, it's complicated.
Are there any way to restart the service (or whaever ) to get my pool back again?. A "systemctl restart xapi" or just xe-toolstack-restart doesn't work. According to xenserver documentation, I must free space (done) and restart the host, but this doc was for 6.5.

I'm asking because I need to increase my pool's CPU resources, the easy way is buy the same processor, but thinking in a more powerful option, RAM and networking features are ok, but compute performance is being starvest by some VM.

I have an old pool, which I had to upgrade some years ago, but no more original model components were available, so I had to buy a new model, new cpu generation, so it became an heterogenous pool. The problem was not the lost of new cpu features, the problem is that time to time, when I performe a live migration VM, it hangs and I must reboot the VM.

Keeping in mind to avoid and heterogeneus pool, I think the safest option is 5220S, because 6226R implies more changes which I unknow in the architecture, maybe new features, that's what I unknow.

Any piece of advice?

I think no, but I'm wondering your opinions.

In my pool I have 5 server with double intel 5217 (8C 3GHz) processors, I'detected that CPU start to be very higth , so thinking in more powefull CPU. Model 5220S is 18C cores at a similar speed. Both, 5220S and 5217 are gold series of "cascade lake" architecture. So, features must be the same, only cores and speed differ. Intel 6226R is another interesting option, quite similar speed and doubles chip cores.

According to citrix, "Combining different CPU models that have identical features" is the 4th type of heterogeneous pool, and "Type 4 represents CPUs with different marketing model names but identical model number, family, and feature flag attributes. Because they have identical attributes, these combinations have always been supported and do not require a mask, but their compatibility has not been obvious when comparing the marketing model names."

Do you think these chips (5220s and 6226R) would mean an heterogeneous pool or not?

In other words, you must empty the host before add it to the primary pool, of course, you can migrate VM from one pool to another. And if your hw is not the same, but similar, you'll have an heterogeneous pool.

5% sounds too much for me, but I'll check it in some populated pools (with host's cpu below 80%) to have a better idea.