# phpman > man > nfs.systemd(7) [NFS.SYSTEMD(7)](https://www.chedong.com/phpMan.php/man/NFS.SYSTEMD/7/markdown) Miscellaneous Information Manual [NFS.SYSTEMD(7)](https://www.chedong.com/phpMan.php/man/NFS.SYSTEMD/7/markdown) ## NAME nfs.systemd - managing NFS services through systemd. ## SYNOPSIS nfs-utils.service nfs-server.service nfs-client.target _etc_ ## DESCRIPTION The _nfs-utils_ package provides a suite of _systemd_ unit files which allow the various services to be started and managed. These unit files ensure that the services are started in the cor‐ rect order, and the prerequisites are active before dependant services start. As there are quite few unit files, it is not immediately obvious how best to achieve certain results. The following subsections attempt to cover the issues that are most likely to come up. ### Configuration The standard systemd unit files do not provide any easy way to pass any command line argu‐ ments to daemons so as to configure their behavior. In many case such configuration can be performed by making changes to _/etc/nfs.conf_ or other configuration files. When that is not convenient, a distribution might provide systemd "drop-in" files which replace the **ExecStart=** setting to start the program with different arguments. For example a drop-in file **sys**‐‐ **temd/system/nfs-mountd.service.d/local.conf** containing [Service] EnvironmentFile=/etc/sysconfig/nfs ExecStart= ExecStart= /usr/sbin/rpc.mountd $RPCMOUNTDOPTS would cause the **nfs-mountd.service** unit to run the _rpc.mountd_ program using, for arguments, the value given for **RPCMOUNTDOPTS** in _/etc/sysconfig/nfs_. This allows for seamless integra‐ tion with existing configuration tools. ### Enabling unit files There are three unit files which are designed to be manually enabled. All others are auto‐ matically run as required. The three are: ### nfs-client.target This should be enabled on any host which ever serves as an NFS client. There is lit‐ tle cost in transparently enabling it whenever NFS client software is installed. ### nfs-server.service This must be enabled to provide NFS service to clients. It starts and configures the required daemons in the required order. ### nfs-blkmap.service The **blkmapd** daemon is only required on NFS clients which are using pNFS (parallel NFS), and particularly using the **blocklayout** layout protocol. If you might use this particular extension to NFS, the **nfs-blkmap.service** unit should be enabled. Several other units which might be considered to be optional, such as _rpc-gssd.service_ are careful to only start if the required configuration file exists. _rpc-gssd.service_ will not start if the _krb5.keytab_ file does not exist (typically in _/etc_). ### Restarting NFS services Most NFS daemons can be restarted at any time. They will reload any state that they need, and continue servicing requests. This is rarely necessary though. When configuration changesare make, it can be hard to know exactly which services need to be restarted to ensure that the configuration takes effect. The simplest approach, which is of‐ ten the best, is to restart everything. To help with this, the **nfs-utils.service** unit is provided. It declares appropriate dependencies with other unit files so that **systemctl** **restart** **nfs-utils** will restart all NFS daemons that are running. This will cause all configuration changes to take effect _except_ for changes to mount options lists in _/etc/fstab_ or _/etc/nfsmount.conf_. Mount options can only be changed by unmounting and remounting filesystem. This can be a disruptive operation so it should only be done when the value justifies the cost. The com‐ mand **umount** **-a** **-t** **nfs;** **mount** **-a** **-t** **nfs** should unmount and remount all NFS filesystems. ### Masking unwanted services Rarely there may be a desire to prohibit some services from running even though there are normally part of a working NFS system. This may be needed to reduce system load to an abso‐ lute minimum, or to reduce attack surface by not running daemons that are not absolutely re‐ quired. Three particular services which this can apply to are _rpcbind_, _idmapd_, and _rpc-gssd_. _rpcbind_ is not part of the _nfs-utils_ package, but it used by several NFS services. However it is **not** needed when only NFSv4 is in use. If a site will never use NFSv3 (or NFSv2) and does not want _rpcbind_ to be running, the correct approach is to run **systemctl** **mask** **rpcbind** This will disable _rpcbind_, and the various NFS services which depend on it (and are only needed for NFSv3) will refuse to start, without interfering with the operation of NFSv4 ser‐ vices. In particular, _rpc.statd_ will not run when _rpcbind_ is masked. _idmapd_ is only needed for NFSv4, and even then is not needed when the client and server agree to use user-ids rather than user-names to identify the owners of files. If _idmapd_ is not needed and not wanted, it can be masked with **systemctl** **mask** **idmapd** _rpc-gssd_ is assumed to be needed if the _krb5.keytab_ file is present. If a site needs this file present but does not want _rpc-gssd_ running, it can be masked with **systemctl** **mask** **rpc-gssd** ## FILES /etc/nfs.conf /etc/nfsmount.conf /etc/idmapd.conf ## SEE ALSO [**systemd.unit**(5)](https://www.chedong.com/phpMan.php/man/systemd.unit/5/markdown), [**nfs.conf**(5)](https://www.chedong.com/phpMan.php/man/nfs.conf/5/markdown), [**nfsmount.conf**(5)](https://www.chedong.com/phpMan.php/man/nfsmount.conf/5/markdown). [NFS.SYSTEMD(7)](https://www.chedong.com/phpMan.php/man/NFS.SYSTEMD/7/markdown)