The title describes the problem pretty well- I was trying to create an NFS share between 3 openstack VMs on a subnet, but the client machines could not see the share on the server.
The ports were opened as per documentation, 2049 and 111 in both udp and tcp. Telnet on both those ports could connect no problem, so why would showmount -e hang until getting a timeout?
Turns out there’s another important port, 20048. I found this out by checking what ports NFS was using on the server machine, with the command
rpcinfo -p . After that it was simply adding a new security group rule.
For reference, the commands I used to create and connect to the share were:
# On Server:
chmod 777 ~/nfsshare
sudo echo "/home/kobi/nfsshare 10.0.0.0/24(rw,sync,no_root_squash)" >> /etc/exports
sudo systemctl restart nfs
showmount -e# On clients
sudo mount -t nfs 10.0.0.7:/home/kobi/nfsshare /home/kobi/nfsshare