Hello there, everyone!
This post explains the process of filtering logging information received by your Syslog server. Please read further down for more details.
BACKGROUND
Are you having trouble monitoring your Huawei network because of the large amount of traps received from each device? In this case, you should be looking for a way to filter the critical data from the informational messages. Luckily, I have the perfect solution for you!
We all know the best way to avoid or fix failures in the network is by keeping all devices under constant observation and monitoring. There are many approaches to this, depending on the size of the network. For a small to medium one, it may be enough to just send the logbuffer information to a Syslog server and verify it periodically but in case of a large network that method could prove inefficient and time consuming. A more efficient approach is to use NMS (Network Monitoring System) software. Because this type of software is fairly complex it offers the means to filter the alarms you receive from your devices and only display the relevant ones. In a particular case, our own product, eSight, offers this type of service through the Alarm Masking feature. Because of this, in the following lines I will present a means for filtering alarms when you only want to use a Syslog server to monitor your network.
Let’s consider the following topology:
As you can see from the network scheme above a Syslog server has been deployed in Area 1. This server contains logbuffer information received from all devices in your network and it may become hard to check the functioning status of each device because of the large number of traps received from each.
To make matters even worse R2 has become faulty and because of a hardware issue interface GE0/0/0 keeps changing between UP/DOWN states. Because this is an OSPF network, any interface status change translates into a lot of OSPF packets sent to peers and many SPT recalculations on the Peer side. As this is now a knows issue and a Swap operation has been scheduled in order to replace the faulty R2 OSPF router I am no longer interested in receiving the related alarms on my Syslog server and I would like to filter them. You can find a few examples of the kind of traps I am dealing with below:
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%INFO/4/SUPPRESS_LOG(l)[21]:Slot=1;Last message repeated 4 times.(InfoID=4284026888, ModuleName=POE, InfoAlias=PORTPW)
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%INFO/4/SUPPRESS_LOG(l)[22]:Last message repeated 19times.(InfoID=1079382037, ModuleName=INFO, InfoAlias=SUPPRESS_LOG)
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%DEFD/4/CPCAR_DROP_LPU(l)[3]:Rate of packets to cpu exceeded the CPCAR limit on the LPU in slot 1. (Protocol=ospf, ExceededPacketCount=08)
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01INFO/4/SUPPRESS_LOG(l)[115]:Last message repeated 45 times
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%DEFD/4/CPCAR_DROP_LPU(l)[3]:Rate of packets to cpu exceeded the CPCAR limit on the LPU in slot 1. (Protocol=ospf, ExceededPacketCount=085)
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%DEFD/4/CPCAR_DROP_LPU(l)[2]:Rate of packets to cpu exceeded the CPCAR limit on the LPU in slot 1. (Protocol=ttl-expired, ExceededPacketCount=02342)
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%INFO/4/SUPPRESS_LOG(l)[2]:Last message repeated 4 times.(InfoID=1880560034, ModuleName=OSPF, InfoAlias=LSA_CHANGE_FREQUENT)
#
As I've already determined, all these traps are related to R2 being faulty. I want all the other devices in my network to stop recording this information and sending it to the Syslog server. Because Huawei devices use the Info-center feature to record information in the logbuffer and then send it to the Syslog server, I will use the info-center filter-id command to enable my Huawei devices to suppress the above logging information.
First of all, please refer to the basic info-center configuration below:
#
info-center enable
info-center loghost 10.0.6.2 channel 2 à this command enables the device to send information to the Syslog server with ip address 10.0.6.2
info-center logbuffer channel logbuffer à this command enables the device to send information to the logbuffer through the info-center module
#
This configuration is already present on all devices in my network. Now, I will need to add the following filter-id commands on all devices, but first I would like to present the general command syntax:
Considering the syntax presented above, I will need to add the following command sequence on all devices:
#
info-center filter-id bymodule-alias POE PORTPW
info-center filter-id bymodule-alias INFO SUPRESS_LOG
info-center filter-id bymodule-alias DEFD CPCAR_DROP_LPU
#
With this configuration in place, I now have customized the logging information stored on my Syslog server and can more efficiently monitor my network.
