I'm using ubuntu 22.04 and have mounted an NFS storage, here is my fstab file
ftpback-bhs5-26.ip-149-56-30.net:/export/ftpbackup/ns524316.ip-xxx-xxx-xxx.net /media/backup nfs vers=4.0 0 0
When checking the ports withnetstat -tunlp, I suddenly found two ports that I did not recognize
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:33781 0.0.0.0:* LISTEN -
tcp6 0 0 :::35929 :::* LISTEN -
fuser -v 33781/tcp output nothing. I searched for a long time but couldn't find where it came from, and finally I remembered that the only recent changes I had made were to mount NFS storage. I umounted it and the port listening disappeared. Why doesn't it show the process name when it's listening? The output of rpcinfo
root@ubuntu:/home/ubuntu# rpcinfo
program version netid address service owner
100000 4 tcp6 ::.0.111 portmapper superuser
100000 3 tcp6 ::.0.111 portmapper superuser
100000 4 udp6 ::.0.111 portmapper superuser
100000 3 udp6 ::.0.111 portmapper superuser
100000 4 tcp 0.0.0.0.0.111 portmapper superuser
100000 3 tcp 0.0.0.0.0.111 portmapper superuser
100000 2 tcp 0.0.0.0.0.111 portmapper superuser
100000 4 udp 0.0.0.0.0.111 portmapper superuser
100000 3 udp 0.0.0.0.0.111 portmapper superuser
100000 2 udp 0.0.0.0.0.111 portmapper superuser
100000 4 local /run/rpcbind.sock portmapper superuser
100000 3 local /run/rpcbind.sock portmapper superuser
Is there a security problem if I don't set up a firewall?
