SNMP is enabled or disabled cluster wide, nodes are not configured individually. You can monitor cluster information from any node in the cluster. Generated SNMP traps correspond to CELOG events. SNMP notifications can also be sent. by using isi event channels create snmpchannel snmp --use-snmp-trap false.
You can configure an event notification rule that specifies the network station where you want to send SNMP traps for specific events. When the specific event occurs, the cluster sends the trap to that server. OneFS supports SNMP version 2c (default), and SNMP version 3 in read-only mode.
OneFS does not support SNMP version 1. Although an option for --snmp-v1-v2-access exists in the OneFS command-line interface (CLI) command isi snmp settings modify, if you turn on this feature, OneFS will only monitor through SNMP version 2c.
You can configure settings for SNMP version 3 alone or for both SNMP version 2c and version 3.
Elements in an SNMP hierarchy are arranged in a tree structure, similar to a directory tree. As with directories, identifiers move from general to specific as the string progresses from left to right. Unlike a file hierarchy, however, each element is not only named, but also numbered.
For example, the SNMP entity iso.org.dod.internet.private.enterprises.isilon.cluster.clusterStatus.clusterName.0 maps to .22.214.171.124.4.1.12126.96.36.199.0. The part of the name that refers to the OneFS SNMP namespace is the 12124 element. Anything further to the right of that number is related to OneFS-specific monitoring.
Management Information Base (MIB) documents define human-readable names for managed objects and specify their data types and other properties. You can download MIBs that are created for SNMP-monitoring of an Isilon cluster from the OneFS web administration interface or manage them using the command line interface (CLI). MIBs are stored in /usr/share/snmp/mibs/ on a OneFS node. The OneFS ISILON-MIBs serve two purposes:
- Augment the information available in standard MIBs
- Provide OneFS-specific information that is unavailable in standard MIBs
ISILON-MIB is a registered enterprise MIB. Isilon clusters have two separate MIBs:
- Defines a group of SNMP agents that respond to queries from a network monitoring system (NMS) called OneFS Statistics Snapshot agents. As the name implies, these agents snapshot the state of the OneFS file system at the time that it receives a request and reports this information back to the NMS.
- Generates SNMP traps to send to an SNMP monitoring station when the circumstances occur that are defined in the trap protocol data units (PDUs).
The OneFS MIB files map the OneFS-specific object IDs with descriptions. Download or copy MIB files to a directory where your SNMP tool can find them, such as /usr/share/snmp/mibs/.
To enable Net-SNMP tools to read the MIBs to provide automatic name-to-OID mapping, add -m All to the command, as in the following example:
snmpwalk -v2c I$ilonpublic -m All <node IP> isilon
During SNMP configuration, it is recommended that you change the mapping to something similar to the following:
isi snmp settings modify -c <newcommunitystring>
If the MIB files are not in the default Net-SNMP MIB directory, you may need to specify the full path, as in the following example. All three lines are a single command.
snmpwalk -m /usr/local/share/snmp/mibs/ISILON-MIB.txt:/usr \ /share/snmp/mibs/ISILON-TRAP-MIB.txt:/usr/share/snmp/mibs \ /ONEFS-TRAP-MIB.txt -v2c -C c -c public isilon