Home servers constantly zombied, and I can't figure out how to fix it

[Alan DeKok]

Adam Bultman wrote:
> After some work getting 2.1.9, and v2.1.x from the git repository up and
> running, I had to go back to 2.1.7-7, that is patched (hopefully,
> anyway!) for the "zombie" problem, via the patch you sent me.  The 2.1.9
> and 2.1.10 versions would die unexpectedly, right around the time the
> "Info: ... ... adding new socket command file
> /var/run/radiusd/radiusd.sock " would scroll through the debug.  I
> couldn't figure it out for the life of me, and strace didn't give me too
> much - it'd just segfault right around that time.

  Don't use strace to track down SEGVs.  It won't help.

  See doc/bugs for instructions on tracking down SEGVs.  Those
instructions work.

>>   Yup.  They can upgrade to a (cough) real radius server. :)
> 
> Turns out, they were a bit stand-offish. They didn't like their radius
> servers being implicated in the mix.  "It's working for 30+ clients, so
> we have no plans to upgrade".

  Exactly... "no one else has noticed a problem, so we're not going to
fix it."

  I guess they don't fix leaks in the roof of their house.  When it
doesn't rain, it doesn't leak.  When it rains, it's too wet to fix the leak.

> One thing I also noticed was that it it doesn't look like freeradius is
> giving it very many tries on a packet before marking the system down.

  FreeRADIUS doesn't retry packets when proxying.  The *NAS* retries
packets.  FreeRADIUS retransmits only when it receives a packet from the
NAS.

> At least, that's the way it appears.  I don't know how to use wireshark
> filters enough to find unacked packets, so I have to do that before I'll
> be able to piece that together.

  Why use wireshark?  The server has a debug mode...

> It is also noteworthy that upon pingscanning their network, I found two
> IP addresses that are up - and I'm getting packet loss to them.  Between
> 4 and 7 percent, which while not a ton, might be enough to cause a
> problem if I'm relaying thousands of packets an hour.

  Yup.

> Thanks for the help, Alan. I appreciate it.

  It's what I do.

  Alan DeKok.