Why are port numbers limited from 1024 to 32767?

[cbergmann]

Hi,

I use a shared hosting service where I can get ports of the host opened to my account. "The port numbers are generated automatically in the range from 40.000 to 61.000 and cannot be chosen arbitrarily." [1].

Unfortunately most zabbix ports (LISTEN_PORT, CONFIG_SERVER_PORT, CONFIG_JAVA_GATEWAY_PORT, CONFIG_LISTEN_PORT) are limited to the range 1024 to 32767.
The lower limit is totally understandable as these are well-known/system ports. The upper limit on the other hand seems arbirary. I would have understood a limit of 49151 which is the border to the dynamic ports but a limit of 65535 would be more flexible in my opinion.

Is there someone here that knowns the reasoning behind this limit?

As a workaround I have prepared a patch (see attached file) that changes the range but that requires me to recompile zabbix for each new version.

Thanks
Clemens


[1]https://manual.uberspace.de/basics-ports/

[cyber]

Maybe it is just a remnant of old times and noone has complained hard enough, so it is not changed..:P You can always submit a ZBX ticket to support and hope it receives enough attention to get into release..

https://support.zabbix.com/projects/ZBX/issues

[RoyK]

Waiting for Zabbix to fix a bug, is quite often time-consuming som I guess the simplest "fix" is to just work around it. Luckily, there's a ton of ways to locally forward ports, be it in userspace or in kernel (with netfilter or similar)
https://unix.stackexchange.com/quest...ort-to-another has som examples