odd issue with sending to broadcast address

odd issue with sending to broadcast address

[Chris Friesen]

It appears that there has been a change in the handling of sending packets to
the broadcast IP address between 2.2 and 2.4.

I have an embedded system that has only local LAN access, no default route to
the net as a whole.  We're running 2.2.17 currently, and we use bootpc to
configure the system.

We're now looking at converting to 2.4 and are running into a problem with
bootpc getting "Network is unreachable" errors.

After some digging, it appears to be due to the fact that I don't have a default
route specified, but this is on purpose.

strace shows that bootpc is trying to run sendto() with a destination of
255.255.255.255, and this works fine on 2.2 and fails on 2.4.  Is this the
desired 2.4 behaviour?

What is the appropriate configuration for my setup?  Do I just add a route to
255.255.255.255?  Can I set it up to broadcast out all devices automatically, or
do I need to do explicit failover management?  Should I be looking to fix bootpc
instead?

Thanks,

Chris


-- 
Chris Friesen                    | MailStop: 043/33/F10  
Nortel Networks                  | work: (613) 765-0557
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