2024-08-26T08:53:59.563Z

<Eugen Block> I just browsed through the docs again and found this section in the [upgrade docs](https://docs.ceph.com/en/latest/cephadm/upgrade/#starting-the-upgrade):
> Cephadm by default reduces max_mds to 1. This can be disruptive for large scale CephFS deployments because the cluster cannot quickly reduce active MDS(s) to 1 and a single active MDS cannot easily handle the load of all clients even for a short time. Therefore, to upgrade MDS(s) without reducing max_mds, the fail_fs option can to be set to true (default value is false) prior to initiating the upgrade
But I haven't used that yet, especially not in production.

2024-08-26T09:36:44.235Z

<Laimis Juzeliūnas> Thanks Eugen, good to know I'm not the only one here noticing this! I'll check details with `fail_fs`for any future possible actions when upgrading. I could not find anything in the Squid releases yet, but have not searched deep enough

2024-08-26T10:16:47.757Z

<Joachim Pierre> Talking about upgrade via UI, what resources do I need to be able to reach on the Internet to make this possible?
We are behind a corporate proxy and need to whitelist any exceptions.

2024-08-26T15:24:28.957Z

<Adam King> I don't think doing it through the UI should change anything as compared to using `ceph orch upgrade...`  so it should just be the container repo of the image being upgraded to. So if you're upgrading to 18.2.4 for example, which the project publishes to [quay.io/ceph/ceph:v18.2.4](http://quay.io/ceph/ceph:v18.2.4), you would need to be able to access [quay.io](http://quay.io). The alternative is to mirror the image on a local repo at which point you tell it to upgrade to that mirrored image and you wouldn't need internet access at all (I think the UI lets you specify the full image if you'd like).