[syslog-ng]SIGHUP res_init feature request

Ted_Rule@flextech.co.uk Ted_Rule@flextech.co.uk
Wed, 4 Sep 2002 15:35:55 +0100

Following on from some experience with DNS misbehaviour on an old syslogd
I was forced to add the ability to force a re-read of resolv.conf upon SIGHUP.
This allowed me to
change the DNS server that a given central syslog server interrogated without
a complete restart of the daemon - which would otherwise have potentially lost

Without this tweak, a given process effectively "caches forever" the contents of
during the first call to gethostbyaddr().

In particular, if I needed to take out a given DNS server for
maintenance/upgrade, I could swing
DNS service elsewhere and avoid disrupting the natural behaviour of the syslog

As far as I can tell syslog-ng doesn't have this feature. As far as I can tell,
adding the feature
merely requires 2 extra lines of code in main.c as per below.

If it meets general approval, perhaps the feature could be added in the next
patch release.




add the following:


#include <resolv.h>      <<<extra line


                if (sighuprecvd) {
                        sighuprecvd = 0;
                        if (!backend->super.reloading) {

                                notice("SIGHUP received, restarting
          res_init();         <<< extra line
                                if (!debug_flag) {
                                        set_error_stream(2, 0);
                                backend->super.reloading = 1;
                                reload_config = 1;
                                r.backend = backend;
                                r.state = -1;
                                /* wait a second to flush buffers */
                                io_callout(&backend->super, 1, &r.super);



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