SNMP - OID issue

[Zolpho]

Hello all,

I'm actually monitoring my RT-AC88U with Zabbix via SNMP.

Every time the PPPoE connection is lost, the OID of the network interfaces changes his value.

Before:

$ snmpwalk -v 2c -c public 192.168.1.1 1.3.6.1.2.1.31.1.1.1.6
IF-MIB::ifHCInOctets.1 = Counter64: 270472404
IF-MIB::ifHCInOctets.2 = Counter64: 0
IF-MIB::ifHCInOctets.3 = Counter64: 0
IF-MIB::ifHCInOctets.4 = Counter64: 0
IF-MIB::ifHCInOctets.5 = Counter64: 1381872212 (eth0)
IF-MIB::ifHCInOctets.6 = Counter64: 0
IF-MIB::ifHCInOctets.7 = Counter64: 39937304 (eth1)
IF-MIB::ifHCInOctets.8 = Counter64: 4214909078 (eth2)
IF-MIB::ifHCInOctets.9 = Counter64: 154397104081
IF-MIB::ifHCInOctets.10 = Counter64: 0
IF-MIB::ifHCInOctets.11 = Counter64: 26506318677 (br0)
IF-MIB::ifHCInOctets.12 = Counter64: 638973834 (ppp0)
IF-MIB::ifHCInOctets.13 = Counter64: 0 (tun1)

After:

$ snmpwalk -v 2c -c public 192.168.1.1 1.3.6.1.2.1.31.1.1.1.6
IF-MIB::ifHCInOctets.1 = Counter64: 270472404
IF-MIB::ifHCInOctets.2 = Counter64: 0
IF-MIB::ifHCInOctets.3 = Counter64: 0
IF-MIB::ifHCInOctets.4 = Counter64: 0
IF-MIB::ifHCInOctets.5 = Counter64: 1381872212 (eth0)
IF-MIB::ifHCInOctets.6 = Counter64: 0
IF-MIB::ifHCInOctets.9 = Counter64: 154397104081
IF-MIB::ifHCInOctets.10 = Counter64: 0
IF-MIB::ifHCInOctets.11 = Counter64: 26506318677 (br0)
IF-MIB::ifHCInOctets.14 = Counter64: 40095543 (eth1)
IF-MIB::ifHCInOctets.15 = Counter64: 4216394384 (eth2)
IF-MIB::ifHCInOctets.17 = Counter64: 1361433921 (ppp0)
IF-MIB::ifHCInOctets.19 = Counter64: 0 (tun1)

On Zabbix web interface:

On Zabbix server:

$ cat zabbix_server.log
14524:20180507:205003.233 item "RT-AC88U:net.if.in.discards[ifInDiscards.12]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.233 item "RT-AC88U:net.if.in.discards[ifInDiscards.13]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.233 item "RT-AC88U:net.if.in.errors[ifInErrors.12]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.233 item "RT-AC88U:net.if.in[ifHCInOctets.12]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.234 item "RT-AC88U:net.if.out.discards[ifOutDiscards.12]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.234 item "RT-AC88U:net.if.out.discards[ifOutDiscards.13]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.234 item "RT-AC88U:net.if.out.errors[ifOutErrors.13]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.234 item "RT-AC88U:net.if.status[ifOperStatus.12]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.288 item "RT-AC88U:net.if.in.errors[ifInErrors.13]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.288 item "RT-AC88U:net.if.out.errors[ifOutErrors.12]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.288 item "RT-AC88U:net.if.speed[ifHighSpeed.12]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.288 item "RT-AC88U:net.if.speed[ifHighSpeed.13]" became not supported: No Such Instance currently exists at this OID

 14524:20180507:205003.336 item "RT-AC88U:net.if.out[ifHCOutOctets.12]" became not supported: No Such Instance currently exists at this OID

 14527:20180507:210003.930 item "RT-AC88U:net.if.type[ifType.12]" became not supported: No Such Instance currently exists at this OID

 14527:20180507:210004.121 item "RT-AC88U:net.if.type[ifType.13]" became not supported: No Such Instance currently exists at this OID

This is a problem because all my graphs and latest data in Zabbix for the network interfaces are lost.

I wonder if it is possible that the router always uses the same OID.

 

[Zolpho]

Dirty solution: rebooting the router - as soon as I receive a notification for ppp down - bring the OID back to the previous values.