snmpd(8n)
Name
snmpd − Simple Network Management Protocol (SNMP) Agent for ULTRIX gateways and hosts
Syntax
/etc/snmpd [ −d debuglevel logfile ]
Description
The SNMP Agent, snmpd, performs SNMP operations on an ULTRIX gateway or host. The daemon, which is started up by an entry in the /etc/services file, sits in the background and listens on SNMP port 161. When the snmpd daemon receives an SNMP packet from a Network Management Station (NMS), the daemon performs SNMP operations on the packet and returns a valid response to the NMS.
The snmpd daemon extracts much of its information from kernel memory. Static variables whose values are not available in the kernel take values from the SNMP configuration file, /etc/snmpd.conf.
SNMP Trap Support
The cold start and authentication failure trap types are supported by snmpd.
The cold start trap type is generated by snmpd when snmpd is restarted. The authentication failure trap type is generated when an attempt at using a community fails. The attempt fails when an unauthorized client tries to use snmpd or the community is used in a way that the community type does not allow.
The snmpd daemon sends traps to all communities specified in the configuration file with a community type traps.
The default is for the snmpd daemon to generate authentication failure traps. However, if the following clause is specified somewhere in the /etc/snmpd.conf file, authentication failure traps are not generated:
no_authen_traps
SNMP Sets
When the snmpd daemon receives a set-request packet, it processes the variables in the packet and verifies that they are valid read-write variables. While performing this verification, the snmpd daemon constructs a linked list of the set requests. After it has completed the verification, it performs the actual set operations on the variables, as if they were being performed simultaneously. If any actual set operation fails, all of the previous set variables from the set-request packet are restored to their old values.
SNMP Supported Variables
For a complete listing of the SNMP Management Information Base (MIB) variables that are supported, see the Guide to Networking.
Options
By default, the snmpd daemon uses the syslog command to record its error messages. However, you can obtain certain debugging and trace information by specifying the −d flag, the appropriate debug level, and a log file for the output on the snmpd command line.
−d debuglevel logfile
Outputs debugging and trace information.
You can specify any one of the following debug levels with the −d flag:
1Print the version number, start time, and exit time of snmpd. Also print out when an SNMP packet is received, the address of the sender, and the packet size in bytes.
2Print out what the snmpd daemon has read from the /etc/snmp.conf file.
3Dump the SNMP packet that the snmpd daemon has just received and is about to process. Also print out the route and interface address that the snmpd daemon is currently looking up. This debug level also dumps the SNMP packet that the server is sending back in response to a received SNMP message.
4Dump the snmp variable tree. Also print out the static bootstrap array of tree information.
The output for a debug level includes the information for all levels including and below the level that you specify. For example, if you specify a debug level of 3, your output includes debug information for levels 3, 2, and 1.
If no debug levels are set, snmpd detaches itself from the controlling terminal and executes in the background.
Restrictions
Not all of the MIB variables are supported.
Only the _mgmt_mib_interfaces_ifTable_ifEntry_ifAdminStatus variable is settable.
Files
/etc/snmpd.conf SNMP configuration file
See Also
snmpext(3n), snmpd.conf(5n), snmpsetup(8n)
RFC 1066—Management Information Base for Network Management of TCP/IP-based Internets
RFC 1067—A Simple Network Management Protocol
Guide to Networking