Home > Article > Operation and Maintenance > What is linux rpc.statd
In Linux, rpc.statd is a process that implements the Network Status Monitoring (NSM) RPC protocol to notify the NFS client when an NFS server restarts abnormally. The syntax is "/sbin/rpc.statd [-F] [-d] [-?] [-n name ] [-o port ] [-p port ] [-V]". The rpc.statd process is automatically started by the nfslock service and does not require user configuration.
#The operating environment of this tutorial: linux7.3 system, Dell G3 computer.
The following RPC background process provides services for NFS
rpc.mountd
: This process accepts mount requests and verifications from NFS clients The requested file system is being exported. This process is automatically started by the NFS service and does not require user configuration.
rpc.nfsd
: This process is the NFS server. It works with the Linux core to meet the dynamic needs of NFS clients, such as providing Server thread for each request. This process corresponds to the nfs service.
rpc.lockd
: An optional process that allows NFS clients to lock files on the server. This process corresponds to the nfslock service.
rpc.statd
: This process implements the Network Status Monitoring (NSM) RPC protocol to notify NFS clients when an NFS server restarts abnormally. This process is automatically started by the nfslock service. No user configuration is required.
rpc.rquotad
: This process provides user quota information for remote users. This process is automatically started by the nfs service and does not require user configuration.
The rpc.statd service implements the NSM (Network Status Monitor) RPC protocol.
This service is somewhat misnamed, as it does not actually provide proactive monitoring as one might suspect; instead, NSM implements a restart notification service.
Used by the NFS file locking service rpc.lockd to enable lock recovery when the NFS server machine crashes and restarts.
Using rpc.statd
In the past, on some Linux distributions, we needed to start rpc.statd separately when starting the NFS server .
This is mainly due to the old Sysvinit system.
Now we will find that starting NFS will automatically start rpc.statd and any other components required for the server to function properly.
systemctl start nfs
Or (depending on the distro)
systemctl start nfs-server
This is also true when enabling the server on startup.
Debian-based distributions such as Ubuntu and Linux Mint will enable NFS as soon as we install it, so there is no need to do this, but enabling the server will look like this:
systemctl enable nfs
or
systemctl enable nfs-server
Again, the exact command depends on the distribution.
"nfs-server" is a Debian-based system.
If we need to customize the behavior of rpc.statd, we can do so using the following options.
Normally, we would not want to run this command alone.
Instead, we will make a copy of the Systemd service file, creating a backup of the original and a new copy to modify freely.
We will then use the following options to change how the service is called from that service file.
Syntax
/sbin/rpc.statd [-F] [-d] [-?] [-n name ] [-o port ] [-p port ] [-V]
Operation
For each NFS client or server to be monitored machine, rpc.statd creates a file in /var/lib/nfs/statd/sm.
When started, it iterates through these files and notifies peerrpc.statd on these machines.
Options
-F
By default, rpc.statd is forked and placed in the background on startup. The
-F parameter tells it to stay in the foreground.
This option is mainly used for debugging purposes.
-d
By default, rpc.statd sends log messages to the system log via syslog(3). The
-d parameter forces it to log verbose output to stderr instead.
This option is mainly used for debugging purposes and can only be used in conjunction with the -F parameter.
-n, --name name
Specify a name for rpc.statd to use as the local host name.
By default, rpc.statd will call gethostname(2) to obtain the local host name.
Specifying the local hostname may be useful for machines with multiple interfaces.
-o, --outgoing-port port
Specify a port for rpc.statd to send outgoing status requests from.
By default, rpc.statd will ask portmap (8) to assign it a port number.
As of this writing, there is no standard port number that portmap always or usually assigns.
Specifying ports may be useful when implementing a firewall.
-p, --port port
Specify the port that rpc.statd listens on.
By default, rpc.statd will ask portmap (8) to assign it a port number.
As of this writing, there is no standard port number that portmap always or usually assigns.
Specifying ports may be useful when implementing a firewall.
-?
Causes rpc.statd to print out command line help and exit.
-V
使 rpc.statd 打印出版本信息并退出。
TCP_WRAPPERS SUPPORT
此 rpc.statd 版本受 tcp_wrapper 库保护。
如果允许客户端使用 rpc.statd,则必须授予客户端访问权限。
要允许来自 .bar.com 域的客户端的连接,我们可以在 /etc/hosts.allow 中使用以下行:
statd: .bar.com
我们必须使用守护程序名称 statd 作为守护程序名称(即使二进制文件具有不同的名称)。
相关推荐:《Linux视频教程》
The above is the detailed content of What is linux rpc.statd. For more information, please follow other related articles on the PHP Chinese website!