# NFS ## Required NFS Server features **File locking**: GitLab **requires** advisory file locking, which is only supported natively in NFS version 4. NFSv3 also supports locking as long as Linux Kernel 2.6.5+ is used. We recommend using version 4 and do not specifically test NFSv3. **no_root_squash**: NFS normally changes the `root` user to `nobody`. This is a good security measure when NFS shares will be accessed by many different users. However, in this case only GitLab will use the NFS share so it is safe. GitLab requires the `no_root_squash` setting because we need to manage file permissions automatically. Without the setting you will receive errors when the Omnibus package tries to alter permissions. Note that GitLab and other bundled components do **not** run as `root` but as non-privileged users. The requirement for `no_root_squash` is to allow the Omnibus package to set ownership and permissions on files, as needed. ### Recommended options When you define your NFS exports, we recommend you also add the following options: - `sync` - Force synchronous behavior. Default is asynchronous and under certain circumstances it could lead to data loss if a failure occurs before data has synced. ## Client mount options Below is an example of an NFS mount point we use on GitLab.com: ``` 10.1.1.1:/var/opt/gitlab/git-data /var/opt/gitlab/git-data nfs4 defaults,soft,rsize=1048576,wsize=1048576,noatime,nobootwait,lookupcache=positive 0 2 ``` Notice several options that you should consider using: | Setting | Description | | ------- | ----------- | | `nobootwait` | Don't halt boot process waiting for this mount to become available | `lookupcache=positive` | Tells the NFS client to honor `positive` cache results but invalidates any `negative` cache results. Negative cache results cause problems with Git. Specifically, a `git push` can fail to register uniformly across all NFS clients. The negative cache causes the clients to 'remember' that the files did not exist previously. ## Mount locations When using default Omnibus configuration you will need to share 5 data locations between all GitLab cluster nodes. No other locations should be shared. The following are the 5 locations you need to mount: | Location | Description | | -------- | ----------- | | `/var/opt/gitlab/git-data` | Git repository data. This will account for a large portion of your data | `/var/opt/gitlab/.ssh` | SSH `authorized_keys` file and keys used to import repositories from some other Git services | `/var/opt/gitlab/gitlab-rails/uploads` | User uploaded attachments | `/var/opt/gitlab/gitlab-rails/shared` | Build artifacts, GitLab Pages, LFS objects, temp files, etc. If you're using LFS this may also account for a large portion of your data | `/var/opt/gitlab/gitlab-ci/builds` | GitLab CI build traces Other GitLab directories should not be shared between nodes. They contain node-specific files and GitLab code that does not need to be shared. To ship logs to a central location consider using remote syslog. GitLab Omnibus packages provide configuration for [UDP log shipping][udp-log-shipping]. ### Consolidating mount points If you don't want to configure 5-6 different NFS mount points, you have a few alternative options. #### Change default file locations Omnibus allows you to configure the file locations. With custom configuration you can specify just one main mountpoint and have all of these locations as subdirectories. Mount `/gitlab-data` then use the following Omnibus configuration to move each data location to a subdirectory: ```ruby user['home'] = '/gitlab-data/home' git_data_dir '/gitlab-data/git-data' gitlab_rails['shared_path'] = '/gitlab-data/shared' gitlab_rails['uploads_directory'] = "/gitlab-data/uploads" gitlab_ci['builds_directory'] = '/gitlab-data/builds' ``` To move the `git` home directory, all GitLab services must be stopped. Run `gitlab-ctl stop && initctl stop gitlab-runsvdir`. Then continue with the reconfigure. Run `sudo gitlab-ctl reconfigure` to start using the central location. Please be aware that if you had existing data you will need to manually copy/rsync it to these new locations and then restart GitLab. #### Bind mounts Bind mounts provide a way to specify just one NFS mount and then bind the default GitLab data locations to the NFS mount. Start by defining your single NFS mount point as you normally would in `/etc/fstab`. Let's assume your NFS mount point is `/gitlab-data`. Then, add the following bind mounts in `/etc/fstab`: ```bash /gitlab-data/git-data /var/opt/gitlab/git-data none bind 0 0 /gitlab-data/.ssh /var/opt/gitlab/.ssh none bind 0 0 /gitlab-data/uploads /var/opt/gitlab/gitlab-rails/uploads none bind 0 0 /gitlab-data/shared /var/opt/gitlab/gitlab-rails/shared none bind 0 0 /gitlab-data/builds /var/opt/gitlab/gitlab-ci/builds none bind 0 0 ``` --- Read more on high-availability configuration: 1. [Configure the database](database.md) 1. [Configure Redis](redis.md) 1. [Configure the GitLab application servers](gitlab.md) 1. [Configure the load balancers](load_balancer.md) [udp-log-shipping]: http://docs.gitlab.com/omnibus/settings/logs.html#udp-log-shipping-gitlab-enterprise-edition-only "UDP log shipping"