net-snmp: reload snmpd on interface events

When applying wireless configuration changes, the ifindex of the
wireless interface(s) change. While snmpd picks up the new interfaces
with the correct index, it does not remove the old ones:

IF-MIB::ifName.23 = STRING: wlan0
IF-MIB::ifName.24 = STRING: wlan1
IF-MIB::ifName.25 = STRING: wlan0
IF-MIB::ifName.26 = STRING: wlan1

This causes problems for monitoring tools that use ifName (or ifDesc) as
interface reference. Add a trigger that reloads snmpd on interface
up/down events so that it will no longer have the old interfaces.

Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>

diff --git a/net/net-snmp/files/snmpd.init b/net/net-snmp/files/snmpd.init
index 000a992d48f5263097a2c3777d512bf028e0b49f..ff780975de8ed62994e4acba13b6afd21ec848ec 100644 (file)
--- a/net/net-snmp/files/snmpd.init
+++ b/net/net-snmp/files/snmpd.init
@@ -230,5 +230,12 @@ stop_service() {
 }
 
 service_triggers(){
+       local script=$(readlink "$initscript")
+       local name=$(basename ${script:-$initscript})
+
+       procd_open_trigger
+       procd_add_raw_trigger "interface.*" 2000 /etc/init.d/$name reload
+       procd_close_trigger
+
        procd_add_reload_trigger 'snmpd'
 }