For NFS content, we will focus on the Analysis and Handling of NFS faults this time. In our daily work and study, we will inevitably encounter some problems. Therefore, we have summarized some specific solutions for these problems.
NFS fault 1. NFSD not started
First, check whether the NFS output list exists. Otherwise, nfsd will not start. You can use the exportfs command to check whether the exportfs command returns the result or the result is incorrect. Check the/etc/exports file.
NFS fault 2. mountd process not started
The mountd process is a Remote Procedure Call (RPC), which responds to the application of the file system that requires the installation of mount on the client. the mountd process finds the/etc/xtab file to find out which file systems can be used by remote clients. in addition, through the mountd process, you can know which file systems have been assembled by remote file systems and the list of remote clients. you can run the rpcinfo command to check whether mountd is properly started. Normally, the output list contains rows like this:
100005 1 udp 1039 mountd
100005 1 tcp 1113 mountd
100005 2 udp 1039 mountd
100005 2 tcp 1113 mountd
100005 3 udp 1039 mountd
100005 3 tcp 1113 mountd
If not, check whether the PORTMAP component is installed.
Rpm-qa | grep portmap
NFS fault 3. fs type nfs no supported by kernel
Kernel does not support the nfs file system. Re-compile the KERNEL to solve the problem.
NFS fault 4. can't contact portmapper: RPC: Remote system error-Connection refused
This error message is displayed because the PORTMAP on the SEVER side is not started.
NFS fault 5. mount clntudp_create: RPC: Program not registered
NFS is not started. You can run the showmout-e host command to check whether the nfs server is started normally.
NFS fault 6, mount: localhost:/home/test failed, reason given by server: Permission denied
This prompt may appear when the client wants to mount the nfs server. It means that the local machine has no permission to mount the directory on the nfs server. The solution is to modify the nfs server.
NFS fault 7. blocked by the firewall
Many people have neglected this reason. in a network environment with strict requirements, we usually close all ports on linux and open them only when any port is needed. NFS uses port 111 by default, so we must first check whether this port is enabled, and also check the TCP_Wrappers settings.