Duo suddenly does not allow NFS mounts

Some more debug info. showmount worked after a while on one machine, but still could not mount

root@utilite-desktop:~# showmount -e 10.10.55.102
Export list for 10.10.55.102:
/c/home *
/c/media (everyone)
/c/backup (everyone)
/c/MRD_FILES (everyone)
/c/KLD_FILES (everyone)
/c/JFD_FILES (everyone)
/c/CSA_FILES (everyone)
/c/Shared_Media (everyone)

root@utilite-desktop:~# mount -o nolock 10.10.55.102:/MRD_FILES /mnt
mount.nfs: Connection timed out

root@utilite-desktop:~# mount -o nolock 10.10.55.102:/c/MRD_FILES /mnt
mount.nfs: Connection timed out

root@utilite-desktop:~# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 12.04.3 LTS
Release: 12.04
Codename: precise
root@utilite-desktop:~# dpkg -l|grep nfs
ii libnfsidmap2 0.25-1ubuntu2 NFS idmapping library
ii nfs-common 1:1.2.5-3ubuntu3.1 NFS support files common to client and server
root@utilite-desktop:~# ps -ef|grep nfs
root 488 2 0 May23 ? 00:00:00 [nfsiod]
root 7642 7609 0 18:36 pts/1 00:00:00 grep --color=auto nfs
root@utilite-desktop:~# ps -ef|grep rpc
root 461 2 0 May23 ? 00:00:00 [rpciod]
root 1478 1 0 May23 ? 00:00:00 rpc.idmapd
root 2300 1 0 May23 ? 00:00:01 rpcbind -w
statd 2586 1 0 May23 ? 00:00:00 rpc.statd -L
root 7644 7609 0 18:36 pts/1 00:00:00 grep --color=auto rpc