osdir.com
mailing list archive F.A.Q. -since 2001!



Subject: execute a command after getting/loosing a
IP-Address? - msg#00011

List: apache.mod-wackamole.general

Mail Archive Navigation:
by Date: Prev Next Date Index by Thread: Prev Next Thread Index

Hi list,

i've set up a round robin/failover scenario with squid.
Wackamole works fine, but my problem is that, in my case,
squid has to bind itself to a special address (not all 0.0.0.0).
So i have to send a kill -HUP to the squid process, after getting a new
IP address, because squid does not listen to this IP.
The problem occurs with any other process, that binds to a special IP and not
to all.

I've put a line in wackamole.c at the end of the Acquire function:
system ("kill -HUP `cat /var/run/squid.pid >/dev/null 2>&1` >/dev/null 2>&1");

But I don't like this very dirty solution, so i wanted to ask,
if there could be a better way to execute a command after
acquiring/releasing an ip address.

I can write the system stuff in c, but I would prefer a more configurable
solution.


Thanks.

Kind regards,



Oliver Fänger


Thread at a glance:

Previous Message by Date:

RE: BPF

Thanks Theo, Basically ... I don't think enabling the BPF (Berkley Packet Filter) in the kernel is going to be an option, due= to the potential security risk .. is there any other way of enabling this .. or will I have to put my hands up and not use Wackamole (sniff) .. ? Your replies are much appreciated. David -----Original Message----- From: wackamole-users-admin@xxxxxxxxxxxxxxxxxx [mailto:wackamole-users-admin@xxxxxxxxxxxxxxxxxx]On Behalf Of Theo Schlossnagle Sent: 20 November 2003 17:43 To: wackamole-users@xxxxxxxxxxxxxxxxxx Cc: Theo Schlossnagle Subject: Re: [Wackamole-users] BPF On Nov 20, 2003, at 7:54 AM, David Carroll wrote: > Do you need to enable BPF in the kernel of each server that runs > Wackamole ? wackamole will open the /dev/bpf### device. I am not sure if that kernel option is required to use the device node, but if it is, then yes it is required for Wackamole to run. // Theo Schlossnagle // Principal Engineer -- http://www.omniti.com/~jesus/ // Postal Engine -- http://www.postalengine.com/ // Ecelerity: fastest MTA on earth _______________________________________________ wackamole-users mailing list wackamole-users@xxxxxxxxxxxxxxxxxx http://lists.backhand.org/mailman/listinfo/wackamole-users

Next Message by Date:

Re: execute a command after getting/loosing a IP-Address?

So, we don't provide any solutions to this problem within Wackamole. However, I'm sure someone else has had to deal with it, and might answer you with something they've already developed. (This is a big holiday in the US, which means a lot of people on the list probably won't be responding for a few days). The solution you proposed is probably the quickest and dirtiest way to get what you want. If you wanted something more powerful, using the same mechanism to run a pair of shell-scripts "Acquire-script" and "Release-script" would give this to you. However, I'd be a little worried about doing so in a general situation, because of the privileges with which Wackamole is run. I wouldn't recommend adding anything too complicated directly to Wackamole, because of timing concerns. You might consider a long-running daemon to handle this failover, that communicates (something along the lines of "Acquire/Release address") with Wackamole via named pipes or another Unix IPC mechanism. Hops this helps, Ryan Oliver Fänger wrote: Hi list, i've set up a round robin/failover scenario with squid. Wackamole works fine, but my problem is that, in my case, squid has to bind itself to a special address (not all 0.0.0.0). So i have to send a kill -HUP to the squid process, after getting a new IP address, because squid does not listen to this IP. The problem occurs with any other process, that binds to a special IP and not to all. I've put a line in wackamole.c at the end of the Acquire function: system ("kill -HUP `cat /var/run/squid.pid >/dev/null 2>&1` >/dev/null 2>&1"); But I don't like this very dirty solution, so i wanted to ask, if there could be a better way to execute a command after acquiring/releasing an ip address. I can write the system stuff in c, but I would prefer a more configurable solution. Thanks. Kind regards, Oliver Fänger _______________________________________________ wackamole-users mailing list wackamole-users@xxxxxxxxxxxxxxxxxx http://lists.backhand.org/mailman/listinfo/wackamole-users -- Ryan W. Caudy Center for Networking and Distributed Systems Department of Computer Science Johns Hopkins University

Previous Message by Thread:

BPF

Hi All, I have a quick question. Do you need to enable BPF in the kernel of each server that runs Wackamole ? Thanks David,

Next Message by Thread:

Re: execute a command after getting/loosing a IP-Address?

So, we don't provide any solutions to this problem within Wackamole. However, I'm sure someone else has had to deal with it, and might answer you with something they've already developed. (This is a big holiday in the US, which means a lot of people on the list probably won't be responding for a few days). The solution you proposed is probably the quickest and dirtiest way to get what you want. If you wanted something more powerful, using the same mechanism to run a pair of shell-scripts "Acquire-script" and "Release-script" would give this to you. However, I'd be a little worried about doing so in a general situation, because of the privileges with which Wackamole is run. I wouldn't recommend adding anything too complicated directly to Wackamole, because of timing concerns. You might consider a long-running daemon to handle this failover, that communicates (something along the lines of "Acquire/Release address") with Wackamole via named pipes or another Unix IPC mechanism. Hops this helps, Ryan Oliver Fänger wrote: Hi list, i've set up a round robin/failover scenario with squid. Wackamole works fine, but my problem is that, in my case, squid has to bind itself to a special address (not all 0.0.0.0). So i have to send a kill -HUP to the squid process, after getting a new IP address, because squid does not listen to this IP. The problem occurs with any other process, that binds to a special IP and not to all. I've put a line in wackamole.c at the end of the Acquire function: system ("kill -HUP `cat /var/run/squid.pid >/dev/null 2>&1` >/dev/null 2>&1"); But I don't like this very dirty solution, so i wanted to ask, if there could be a better way to execute a command after acquiring/releasing an ip address. I can write the system stuff in c, but I would prefer a more configurable solution. Thanks. Kind regards, Oliver Fänger _______________________________________________ wackamole-users mailing list wackamole-users@xxxxxxxxxxxxxxxxxx http://lists.backhand.org/mailman/listinfo/wackamole-users -- Ryan W. Caudy Center for Networking and Distributed Systems Department of Computer Science Johns Hopkins University
blog comments powered by Disqus

Home | News | Sitemap | FAQ | advertise | OSDir is an Inevitable website. GBiz is too!