Add ruby 3.1 update to README.UPDATERS

dist/README.UPDATERS

@@ -1,3 +1,48 @@
+For Updaters from OBS 2.10 to OBS 2.11
+======================================
+
+Note: Update from OBS 2.5 should also work, but it is not fully tested.
+      A direct update from OBS 2.4 or older will not work.
+      It's recommended to wait for all pending delayed jobs to be processed before
+      creating a DB dump or running the migrations.
+      To see the number of pending delayed jobs run
+
+        cd /srv/www/obs/api
+        bin/bundle exec bin/rails r -e production "puts Delayed::Job.count" RAILS_ENV=production
+
+  1) Remove the OBS 2.10 Repository
+
+        zypper rr OBS:Server:2.10
+
+  2) Add the OBS 2.11 Repository and update repository cache
+
+        zypper ar http://download.opensuse.org/repositories/OBS:/Server:/2.11/$YOUR_DISTRIBUTION/OBS:Server:2.11.repo
+        zypper ref
+
+  3) Update packages
+
+        zypper dup --from OBS_Server_2.11
+
+    NOTE: You may need to switch also your base distribution to a newer version. Adapt all repositories for that and do an
+
+        zypper dup
+
+      instead of the above command
+
+  4) Migrate database
+
+        cd /srv/www/obs/api/
+        RAILS_ENV="production" bin/rails db:migrate:with_data
+
+  5) Change to ruby3.1
+
+        edit /etc/apache2/conf.d/mod_passenger.conf:
+
+        PassengerRuby "/usr/bin/ruby.ruby3.1"
+
+  6) Reboot your system to restart all OBS components
+
+
 For Updaters from OBS 2.9 to OBS 2.10
 =====================================