mountd: refused mount request: unmatched host

mountd: refused mount request: unmatched host
Most likely the problem is on /etc/exports, add your IP or range after the directory you want to share.
vim /etc/exports
/opt/smr 172.17.0.0/16(rw,sync,no_root_squash)
Check also
/etc/hosts.allow
/etc/hosts.deny
Good material for troubleshooting:
http://www.cs.bgu.ac.il/~arik/usail/network/nfs/tips.html
http://osr507doc.sco.com/en/PERFORM/NFS_monitoring.html
http://tldp.org/HOWTO/NFS-HOWTO/troubleshooting.html
http://osr507doc.sco.com/en/PERFORM/NFS_rsc.html