How to determine if mountd is running on reserved ports?

[Duke Nguyen]

rpcinfo returns the following info:
/etc/rc.config.d # rpcinfo -p |grep mountd
100005 1 udp 49213 mountd
100005 3 udp 49213 mountd
100005 1 tcp 49163 mountd
100005 3 tcp 49163 mountd

Are these ports reserved? I am NOT using the "-p" option when starting mountd.

I was told that these ports are unreserved and cound pose a security risk. I've read on another post that these ports are privileged ports and root can only access these ports...can someone please confirm for me?

Thanks.

[G. Vrijhoeven]

Hi Duke,

If you read man rpcinfo:

-p Run from unreserved ports.The option restores old default behavior on HP-UX. .....

So if you start mountd without the -p option you run on reserved ports.

Hope this will help,

Gideon

[harry d brown jr]

Download "lsof" from:
http://hpux.cs.utah.edu/hppd/hpux/Sysadmin/lsof-4.55/

and it will tell you what application has what sockets open, plus its one kick-butt tool for other things as well!


live free or die
harry

[Duke Nguyen]

Is it true that ports greater than 1023 are all reserved ports? And that only root can access reserved ports on the local machine?

[harry d brown jr]

No. Typically we like to say that reserved root ports are less than 1023, but this is not always the case, ie: WEB servers using ports 80 and 443.

live free or die
harry

[Duke Nguyen]

Thanks Harry...but I'm a little confused right now.
If mountd is NOT being started with the "-p" option, then how come mountd uses ports in the 49213 range? Shouldn't mountd use reserved ports under 1023 since the "-p" is not being used?

[James R. Ferguson]

Hi Duke:

RFC 1700 defines "well-known" or "assigned" ports as those in the range 0-1023. Ports in the range 1024-65535 are known as "registered" ports. That is, their usage is not controlled, but their intended use is officially documented.

Prior to HP-UX 10.30, port numbers were chosen from the range 1024 to 5000 whenever a program let the system allocate ???anonoymously??? (bind to port number zero). Starting with HP-UX 10.30, the "anonymous" range moved to 49152-65535, by default.

In 11.x releases, the maximum automatically assigned port number can be changed with the ???tcp_largest_anon_port??? and ???udp_largest_anon_port??? using ???ndd???

Regards!

...JRF...

[Duke Nguyen]

Does mountd running on ports 49213 range cause a security concern? If so, would running mountd with the "-p" option make mountd use a port below 1023? Thanks in advance.