Conflicting assignment of priviledged ports on boot, once again
what is the collected wisdom nowadays on how to avoid random port
conflicts when booting?
In 2005 I wrote:
"On boot some daemons (like nis/ypbind) obtain priviledged ports
via portmap/bindresvport(). Portmap assigns ports that are not in use
at the time of request, usually above 600. This strategy sometimes
conflicts with daemons that rely on fixed ports and that
start after ypbind (like cups, slapd): they find that their port
is already in use."
(My description then was not accurate, since portmap only registers
port bindings; but otherwise the issue remains.)
I went on to suggest that Debian adopt the portreserve/portrelease
approach [http://cyberelk.net/tim/software/portreserve/], which would
solve many problems. In the ensuing discussion people acknowledged
that there is a problem and that portreserve would help in most
situations, but apparently it was not considered serious enough.
In 2009, I'm still bitten by this problem, and it seems that not much
has changed in Debian. Portreserve is available as package, but no
service drops on installation the required info in /etc/portreserve .
(It seems that Fedora in adopting this approach, though
What is currently the expert way to avoid/handle such port conflicts