Solaris System Management Agent Administration Guide

Chapter 3 Working with the System Management Agent

This chapter describes how to manage common operations with the System Management Agent. This chapter contains material on the following topics:

Starting and Stopping the System Management Agent

Start or stop the SMA by starting or stopping the snmpd daemon. Numerous options are available for starting or stopping the daemon, but several of these options override the snmpd.conf and snmp.conf files. The recommended way to start and stop the System Management Agent is to use the svcadm command as described in this section. Further information on the snmpd daemon can be found in the snmpd(1M) man page.

Note –

As a standard SNMP agent, the System Management Agent must run on port 161. If another process is running on port 161, the System Management Agent does not start.

To Start the System Management Agent

Once the svcadm command has launched the System Management Agent on your system, the snmpd daemon always starts at boot time during the Solaris system boot. If you are using other agents, you might want to prevent the snmpd daemon from starting at boot time, which initializes the System Management Agent. If you want to prevent the snmpd daemon from starting at boot time, see To Prevent The System Management Agent Initializing at Boot Time.

As root, start the SMA service.

# svcadm enable svc:/application/management/sma:default

Check whether errors occurred in attempting to start the System Management Agent by examining the /var/log/snmpd.log file.

If the log file reports that the port 161 is occupied, follow the procedure described in To Check Whether Another Process Is Running on the SMA Port.

To Restart the System Management Agent

To enable changes made to the main SMA configuration file, /etc/sma/snmp/snmpd.conf, a signal must be sent to the SMA daemon, snmpd. This signal reads the changes to snmpd.conf and restarts the System Management Agent.

As root, restart the SMA service.

# svcadm restart svc:/application/management/sma:default

This method is the recommended way to restart the System Management Agent.

To Stop the System Management Agent

As root, stop the SMA service.

# svcadm disable svc:/application/management/sma:default

Common Operations With the System Management Agent

To Check Whether Another Process Is Running on the SMA Port

Port 161 is reserved for the System Management Agent. For more information, see Managing Configuration With the Main Configuration File.

Use the netstat command:

# netstat -anv|grep 161

If a value of 161 is returned, a process is already bound to port 161.

To View the Status of the Agent

As root, get the service status.

# svcs svc:/application/management/sma:default

A typical response to this command is shown:

STATE          STIME    FMRI
online         Aug_24   svc:/application/management/sma:default

To See Which MIBs Are Initialized

Use one of the following methods to list those MIBs that are initialized when the SMA is started.

Examine the debug trace that is produced by running the following command:
# /usr/sfw/sbin/snmpd -Dregister_mib -Dmib_init -L

Alternatively, use the net-snmp-config command to see a list of those modules that are compiled.
# /usr/sfw/bin/net-snmp-config --snmpd-module-list

To Check the Disk Space on a Local or Remote Machine

First find the total disk space of the disk, then find how much of this space is used. The difference between these two totals is the available disk space.

Find the number of disks that are available on a given host.

# snmpwalk -v1 -c public hostname HOST-RESOURCES-MIB::hrStorageIndex

This command returns a list of disks on the host, hostname:

HOST-RESOURCES-MIB::hrStorageIndex.1 = INTEGER: 1
HOST-RESOURCES-MIB::hrStorageIndex.2 = INTEGER: 2
HOST-RESOURCES-MIB::hrStorageIndex.3 = INTEGER: 3
HOST-RESOURCES-MIB::hrStorageIndex.4 = INTEGER: 4
HOST-RESOURCES-MIB::hrStorageIndex.5 = INTEGER: 5
HOST-RESOURCES-MIB::hrStorageIndex.6 = INTEGER: 6
HOST-RESOURCES-MIB::hrStorageIndex.7 = INTEGER: 7
HOST-RESOURCES-MIB::hrStorageIndex.8 = INTEGER: 8
HOST-RESOURCES-MIB::hrStorageIndex.9 = INTEGER: 9
HOST-RESOURCES-MIB::hrStorageIndex.10 = INTEGER: 10
HOST-RESOURCES-MIB::hrStorageIndex.101 = INTEGER: 101
HOST-RESOURCES-MIB::hrStorageIndex.102 = INTEGER: 102

The disk is indicated by the index number:

HOST-RESOURCES-MIB::hrStorageIndex.1 = INTEGER: 1

This output represents disk 1, /dev/dsk/c0t0d0s0

Use the snmpget command to retrieve the total storage space for that disk.

The following command would retrieve the total storage space for disk 1:
# snmpget -v1 -c public hostname HOST-RESOURCES-MIB::hrStorageSize.1
This command returns the total disk space at the end of the line:
HOST-RESOURCES-MIB::hrStorageSize.1 = INTEGER: 2561695

View a list of the disk space used by each disk.

# snmpwalk -v1 -c public hostname HOST-RESOURCES-MIB::hrStorageUsed

HOST-RESOURCES-MIB::hrStorageUsed.1 = INTEGER: 2121747
HOST-RESOURCES-MIB::hrStorageUsed.2 = INTEGER: 0
HOST-RESOURCES-MIB::hrStorageUsed.3 = INTEGER: 0
HOST-RESOURCES-MIB::hrStorageUsed.4 = INTEGER: 0
HOST-RESOURCES-MIB::hrStorageUsed.5 = INTEGER: 11
HOST-RESOURCES-MIB::hrStorageUsed.6 = INTEGER: 48
HOST-RESOURCES-MIB::hrStorageUsed.7 = INTEGER: 1892576
HOST-RESOURCES-MIB::hrStorageUsed.8 = INTEGER: 0
HOST-RESOURCES-MIB::hrStorageUsed.9 = INTEGER: 130565552
HOST-RESOURCES-MIB::hrStorageUsed.10 = INTEGER: 26036932
HOST-RESOURCES-MIB::hrStorageUsed.101 = INTEGER: 55995
HOST-RESOURCES-MIB::hrStorageUsed.102 = INTEGER: 17171

Use the snmpget command to view the storage used by the disk in question.

# snmpget -v1 -c public hostname HOST-RESOURCES-MIB::hrStorageUsed.1

This command returns the disk space used on disk 1:

HOST-RESOURCES-MIB::hrStorageUsed.1 = INTEGER: 2121747

Subtract this figure from the total disk space to find the available disk space:

2561695 – 2121747 = 439948

The `snmpnetstat` command

In the same way as you would use the netstat command, you can check the status of the network using the System Management Agent with the snmpnetstat command.

To show the state of all sockets, use the snmpnetstat command with the –a option. This option provides the default display, showing all active sockets, except those used by server processes.

# snmpnetstat -v 2c -c public -a testhost

The following information, including local and remote addresses, and protocols, is typically displayed:

Active Internet (tcp) Connections (including servers)
     Proto Local Address Foreign Address (state)
     tcp   *.echo        *.*             LISTEN
     tcp   *.discard     *.*             LISTEN
     tcp   *.daytime     *.*             LISTEN
     tcp   *.chargen     *.*             LISTEN
     tcp   *.ftp         *.*             LISTEN
     tcp   *.telnet      *.*             LISTEN
     tcp   *.smtp        *.*             LISTEN

     Active Internet (udp) Connections
     Proto Local Address
     udp   *.echo
     udp   *.discard
     udp   *.daytime
     udp   *.chargen
     udp   *.time

To show the state of network interfaces, use the snmpnetstat command with the –i option. This option provides a statistics table that shows packets transferred, errors, and collisions as well as network addresses of the interface and the maximum transmission units (MTU).

# snmpnetstat -v 2c -c public -i testhost

The following table, including local and remote addresses, and protocols, is typically displayed:

Name Mtu  Network   Address  Ipkts     Ierrs  Opkts  Oerrs Queue
     eri0 1500 10.6.9/24 testhost 170548881 245601 687976 0     0
     lo0  8232 127      localhost 7530982   0      7530982 0    0

Note –

The Ipkts, or incoming packets, value reported by the snmpnetstat command is not identical to that reported by the netstat command. The snmpnetstat command displays the total number of unicast, multicast and broadcast packets. The netstat command displays the total number of unicast and multicast packets, omitting broadcast packets.

Resource Usage

The resident size of the snmpd daemon depends on how the SMA is used.

The snmpd daemon dynamically allocates memory for certain MIB table data, for example, when you have defined printers, and then walk the Host Resource MIB. The resident size of the snmpd daemon can increase by up to 100Kbytes depending upon the number of printers you have defined.

JDMK Interoperability

Java^TM Development Management Kit (JDMK) implements the JMX specifications and in addition, enables SNMP based instrumentation within the JDMK agent infrastructure. Like the System Management Agent, JDMK also supports the following standards:

SNMPv3
SNMPv2c
SNMPv1
USM
Proxying

JDMK does not support AgentX.

Though both JDMK and the SMA address SNMP instrumentation, JDMK is very suited to Java based environments. The SMA is more suited to native C based implementations.

Configuration and Proxying With JDMK

In Sun systems where both JDMK and the SMA are present, the SMA by default resides on port 161. JDMK agents can publish their SNMP MIBs by being proxied from the SMA. Proxying can be set up using the proxy forwarding mechanism within the SMA. See Example 3–1.

Security must to be handled by the master agent, which is the SMA, and by the proxied JDMK agent. Security parameters that are contained in the proxy definition are forwarded to the proxied JDMK agent. If the request passes the SMA authentication and authorization and is forwarded to its proxy handler, then the dispatched request is proxied to the JDMK agent. The JDMK agent has its own local datastore that authorizes or rejects the message.

If several JDMK agents have the same MIB, SNMP contexts must be used in conjunction with proxying to differentiate between different instances of the same MIB. The context name can be based on the process ID. Alternatively, the context name can be based on the port on which the JDMK agent is running.

Example 3–1 Adding a JDMK Proxy Statement

Incoming requests for the JDMK agent can be received by the System Management Agent and then proxied to the JDMK agent. Set JDMK proxy entries using the proxy token in the main snmpd.conf configuration file. Add a proxy statement, such as the following:

# proxy --Cn jdmkMib -v3 -a MD5 -u
 SecureUser -l authNopriv -A 12345678 localhost:10161  1.3.6.1.4.1.42.5000.2

In this example, a MIB is running on port 10161 and registers the MIB region 1.3.6.1.4.1.42.5000 under the context jdmkMib. The user, who is named SecureUser, must also exist in the JDMK USM. The SecureUser user must allow a security level of auth with HMACMD5 as the authentication algorithm. For more information on authentication algorithms, see Authentication Protocol Algorithms.

See the snmpd.conf(4) man page for more information. For more information about how proxying is set up, see Proxy Handling for Solstice Enterprise Agents Requests.