No warning is issued for invalid options that are supplied with the mount command. This procedure helps determine whether the options that were supplied either on the command line or through the /etc/vfstab file were valid.
For the example in this procedure, assume that the following command has been run:
$ mount -F nfs -o ro,vers=2 bee:/export/share/local /mnt
$ nfsstat -m
/mnt from bee:/export/share/local
Flags: vers=2,proto=tcp,sec=sys,hard,intr,dynamic,acl,rsize=8192,wsize=8192,
retrans=5
The file system from the bee server has been mounted with the protocol version set to 2. The nfsstat command does not display information about all of the options. However, using the nfsstat command is the most accurate way to verify the options.
The mount command does not allow invalid options to be added to the mount table. Therefore, verify that the options that are listed in the file match the options that are listed on the command line. In this way, you can check the options that are not reported by the nfsstat command.
$ grep bee /etc/mnttab bee:/export/share/local /mnt nfs ro,vers=2,dev=2b0005e 859934818