Add bucket size error to troubleshooting docs

CHANGELOG.md

@@ -5,7 +5,7 @@ omnibus-gitlab repository.
 8.9.0
-- Fix NGINX not starting with long server names by making the bucket size configurable and defaulting it to 64 bytes
+- Make NGINX server_names_hash_bucket_size configurable and default it to 64 bytes
 8.8.2

doc/README.md

@@ -76,6 +76,7 @@ Omnibus is a way to package different services and tools required to run GitLab,
 - ['Short read or OOM loading DB' error](common_installation_problems/README.md#short-read-or-oom-loading-db-error).
 - ['pg_dump: aborting because of server version mismatch'](settings/database.md#using-a-non-packaged-postgresql-database-management-server)
 - ['Errno::ENOMEM: Cannot allocate memory' during backup or upgrade](common_installation_problems/README.md#errnoenomem-cannot-allocate-memory-during-backup-or-upgrade)
+- [NGINX error: 'could not build server_names_hash'](common_installation_problems/README.md#nginx-error-could-not-build-server_names_hash-you-should-increase-server_names_hash_bucket_size)
 ## Omnibus GitLab developer documentation

doc/common_installation_problems/README.md

@@ -437,6 +437,18 @@ If GitLab runs fine when not upgrading or running a backup, then adding more swa
 should solve your problem. If you see the server using swap during normal usage,
 you can add more RAM to improve performance.
+### NGINX error: 'could not build server_names_hash, you should increase server_names_hash_bucket_size'
+
+If your external url for GitLab is longer than the default bucket size (64 bytes),
+NGINX may stop working and show this error in the the logs. To allow larger server
+names, double the bucket size in `/etc/gitlab/gitlab.rb`:
+
+```ruby
+nginx['server_names_hash_bucket_size'] = 128
+```
+
+Run `sudo gitlab-ctl reconfigure` for the change to take effect.
+
 [CAcert.org]: http://www.cacert.org/
 [certificate link shell script]: https://gitlab.com/snippets/6285
 [script source]: https://www.madboa.com/geek/openssl/#verify-new