Hi all, after reading the following reference links on DataMiner docs, I'd like to ask some True/False questions to check my understanding of how to configure the port that a DMA will listen for SNMP traps. If the answer to my question is False, please state help to state the truth 🙂
Reference link:
Changing SNMP agent ports | DataMiner Docs
Interaction between SNMP manager and SNMP agent | DataMiner Docs
DataMiner.xml | DataMiner Docs
#1 By default, a DMA will listen on UDP port 162 for all SNMP trap for all versions (1, 2 and 3). This is done using the SNMP++ process. The SNMPTRAP process is stopped. True or False?
#2 By specifying the <SNMPv3 trapPort="16261"/> line in DataMiner.xml we can configure a DMA to listen to port 16261 for SNMPv3 traps using the SNMP++ process. When this happens, the SNMPTRAP process is started and the DMA will use the SNMPTRAP process to listen on port 162 for SNMPv2 and SNMPv1 traps. We can then further configure the port that SNMPTRAP process listens to by configuring the line starting "snmptrap" in 'C:\Windows\System32\drivers\etc\services' file. True or False?
#3 The <SNMPv3 trapPort="16261"/> update done to DataMiner.xml does not sync across to other DMAs in a cluster. True or False?
#4 The <SNMPv3 trapPort="16261"/> update done to DataMiner.xml does not sync across to the other DMA in a failover pair. True or False?
#5 Changes to the DataMiner.xml file will require a DMA restart to take effect. Changes to the line starting "snmptrap" in 'C:\Windows\System32\drivers\etc\services' file will also require a DMA restart to take effect. True or False?
Hi Bing,
- Yes, if the SNMPTrap process is running while the DMA starts, then SLSNMPManager will attempt to stop it to take port 162.
- Although I could find references to the SNMPTrap process being stopped (see item 1.), I couldn't find any references in the code to start the SNMPTrap process. However, after having it stopped manually and configuring the SNMPv3 trapPort, the process was started when starting the DMA. I haven't used the services file before, but it looks like you could change the SNMPTrap service's port that way.
- Yes, as each DataMiner.xml file contains unique information like the agent ID, it is not synced to other agents.
- There's no exception to item 3. for failover pairs to my knowledge.
- DataMiner does not actively monitor for file changes and assumes they are not changed during runtime. This may lead to scenarios where changes you made to the file manually are overwritten by the agent when it is active. As such, a restart is necessary to have DataMiner configured differently. Although some XML files can be updated while the agent is active by sending a notify, but this doesn't work for configuration files as the agent is currently not able to reconfigure its active state. This does work for e.g. element configuration if the element is then also restarted.
In a similar vain, I believe the SNMPTrap process needs to be restarted if the services file is changed. I think SLSNMPManager, and thus the DMA, can stay active while the SNMPTrap process is restarted.