determining server-supported NFS version from the client

Question

Is there a way to determine which version of the NFS protocol a particular server is running just by mounting it as a client? I'm trying to figure out if a server supports NFS v4, but I can't figure out an easy way to do this.

Answer 1

You can use: rpcinfo -p HOSTNAME.

Here's an example of me checking a local box on my network called "mythicism":

$ rpcinfo -p mythicism<br>
   program vers proto   port  service<br>
    100000    2   tcp    111  portmapper<br>
    100000    2   udp    111  portmapper<br>
    100011    1   udp    732  rquotad<br>
    100011    2   udp    732  rquotad<br>
    100011    1   tcp    733  rquotad<br>
    100011    2   tcp    733  rquotad<br>
    100024    1   udp  34431  status<br>
    100024    1   tcp  32819  status<br>
    100021    1   udp  40971  nlockmgr<br>
    100021    3   udp  40971  nlockmgr<br>
    100021    4   udp  40971  nlockmgr<br>
    100021    1   tcp  34035  nlockmgr<br>
    100021    3   tcp  34035  nlockmgr<br>
    100021    4   tcp  34035  nlockmgr<br>
    100003    2   udp   2049  nfs<br>
    100003    3   udp   2049  nfs<br>
    **100003    4   udp   2049  nfs**<br>
    100003    2   tcp   2049  nfs<br>
    100003    3   tcp   2049  nfs<br>
    **100003    4   tcp   2049  nfs**<br>
    100005    1   udp  49571  mountd<br>
    100005    1   tcp  52263  mountd<br>
    100005    2   udp  49571  mountd<br>
    100005    2   tcp  52263  mountd<br>
    100005    3   udp  49571  mountd<br>
    100005    3   tcp  52263  mountd<br>