Installing Net-SNMP on Solaris OS

Introduction:
Sun OS versions previous to Solaris10 come configured with the Sun SNMP agent. Solaris has started shipping Net-SNMP with Solaris10 as an alternative to the Sun SNMP agent, this guide is designed to offer a road-map for installing Net-SNMP on versions older than Solaris10 so that users can utilize both the inclusion of the HOST-MIB Tree (Disk and CPU monitoring) and the use of SNMPv3 (encryption of SNMP traffic over a network) within these previous OS's (capability unavailable in the Sun SNMP agent).

Check For Sun SNMP Agent:
Before we start we need to check for the existence of the Sun SNMP agent and turn it off if it is running.

To do so run the following command from the command line:

Code:

ps -ef | grep snmp

If the Sun agent is running you will see output similar to the following:

Code:

    root 10765     1  0   Sep 23 ?        0:00 /usr/lib/dmi/snmpXdmid -s builder-solaris
    root 10756     1  0   Sep 23 ?        0:00 /usr/lib/dmi/snmpXdmid -s builder-solaris
    root 10725     1  0   Sep 23 ?       18:41 /usr/lib/snmp/snmpdx -y -c /etc/snmp/conf

If the Net-SNMP agent has already been installed and is running you will alternatively see output similar to this:

Code:

    root  4035     1  0 16:08:12 ?        0:03 /usr/local/sbin/snmpd

If no agent is currently running you receive an empty set output.

Turn Off Sun Agent:

In the event that you do have a running sun Agent, it can be turned off using the following commands:

Code:

/etc/rc3.d/S76snmpdx stop
/etc/rc3.d/S77dmi stop

Once you have stopped the process, make sure that you have nothing else running on UPD ports 161 or 162, this can be checked by running the following commands:

Code:

netstat -an | grep 161
netstat -an | grep 162

Assuming nothing is currently running, both should return an empty set. If connection information is returned you will need to clear these ports before you can proceed.

To disable Sun's SNMP

In the event reboot or restart sun Agent will start running due to service; to avoid so we need to disable the Sun SNMP Agent  

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

Installing Net-SNMP Agent
The Net-SNMP package can be installed from packages or built locally on a system from source.
Installing from packages involves the following steps:

Retrieve the package:
For demo purpose we are going to install Net-SNMP from packages available at: http://www.sunfreeware.com/

To retrieve the package you are going to want to use the linux FTP client to download the archive. This can be achieved using the following set of commands:

Code:

>       cd /tmp
>       ftp ftp.sunfreeware.com
ftp>   anonymous
ftp>   (your email address)
ftp>   bin
ftp>   cd pub/freeware/sparc/9/
ftp>   get netsnmp-5.4.2.1-sol9-sparc-local.gz
ftp>   quit
>       gunzip netsnmp-5.4.2.1-sol9-sparc-local.gz
>       pkgadd -d netsnmp-5.4.2.1-sol9-sparc-local

Keep in mind that this set of instructions is for Solaris 9, different versions of Solaris will require slightly different paths and filenames (IE sol9, sparc/9/), different build numbers will also require slightly different filenames (IE 5.4.2.1).

It should also be mentioned that you can also always alternatively build these packages from source (in fact this is the Net-SNMP preferred way), for detailed instructions regarding building the Net-SNMP package from source please visit: http://www.net-snmp.org/docs/README.solaris.html .

Configuring Net-SNMP

Once Net-SNMP has been successfully installed you are going to need to configure the agent by creating an snmpd.conf file and copying it over to the /usr/local/share/snmp/ directory.

This can be accomplished by completing the snmp configuration wizard:

Code:

> cd /tmp
> snmpconf -g basic_setup
[Complete Questionair]
>cp snmpd.conf /usr/local/share/snmp/

Alternatively for a simple setup you can copy and paste the following into a file located at /usr/local/share/snmp/snmpd.conf (SNMPv1 & v2 with community string 'public'):

Code:

###########################################################################
# SECTION: Access Control Setup
#
#   This section defines who is allowed to talk to your running
#   snmp agent.

# rocommunity: a SNMPv1/SNMPv2c read-only access community name
#   arguments:  community [default|hostname|network/bits] [oid]

rocommunity  public

To test that the configuration has worked you will want to run the following set of commands from the command line:

Code:

/usr/local/sbin/snmpd
snmpwalk -v 2c -c public localhost

If the agent is running correctly you are going to see an snmpwalk output dump to your screen, which should look similar to this:

Code:

SNMPv2-MIB::snmpOutBadValues.0 = Counter32: 0
SNMPv2-MIB::snmpOutGenErrs.0 = Counter32: 0
SNMPv2-MIB::snmpOutGetRequests.0 = Counter32: 0
SNMPv2-MIB::snmpOutGetNexts.0 = Counter32: 0
SNMPv2-MIB::snmpOutSetRequests.0 = Counter32: 0
SNMPv2-MIB::snmpOutGetResponses.0 = Counter32: 2826
SNMPv2-MIB::snmpOutTraps.0 = Counter32: 0
SNMPv2-MIB::snmpEnableAuthenTraps.0 = INTEGER: disabled(2)
SNMPv2-MIB::snmpSilentDrops.0 = Counter32: 0
SNMPv2-MIB::snmpProxyDrops.0 = Counter32: 0

For the Solaris 10 which comes with pre installed Net-SNMP daemon; program locates at /usr/sfw/sbin/snmpd, and configure file of snmpd saved with the name snmpd.conf at /etc/sma/snmp. Use svcadm to start of stop snmpd:

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

Log File
if there's any error or warning messages, see the file /var/svc/log/application-management-sma\:default.log. The default log file of snmpd is/var/log/snmpd.log.

Configuration file
We may use /etc/sma/snmp/snmpd.conf.save as the working configure file to test wheather our snmpd daemon is ok.
#cp /etc/sma/snmp/snmpd.conf.save /etc/sma/snmp/snmpd.conf
#svcadm restart sma

P.S. There's another file also named as snmpd.conf stored in /var/sma_snmp directory, and which is called persistent storage file. The persistent storage file, /var/sma_snmp/snmpd.conf, contains USM security information and any MIB components that are set for persistent storage. This file also contains the engineID and the engineID boots. This persistent storage file is automatically updated when the System Management Agent starts. When the System Management Agent stops, the snmpusm and snmpvacm utilities write user security information to this storage file.

Using the AgentX Protocol
The AgentX protocol is supported in the System Management Agent. By default, the System Management Agent ships with a secure profile, that is, read–only access. AgentX allows interaction with third party subagents, provided that these subagents support AgentX over Unix Domain Sockets. For security reasons, AgentX is not supported over TCP/UDP. For more information on the AgentX protocol, see http://www.ietf.org/rfc/rfc2741.txt Edit the main /etc/sma/snmp/snmpd.conf configuration file to configure the System Management Agent to use the AgentX protocol. By default, the AgentX protocol is disabled. The following procedure describes how to enable the AgentX protocol. To enable the AgentX protocol add the following to /etc/sma/snmp/snmpd.conf file:

master agentx

restart the sma (system management agent).
# svcadm restart svc:/application/management/sma:default

Using the SMA
To view the status of the agent
# svcs svc:/application/management/sma:default

To See Which MIBs Are Initialized
# /usr/sfw/sbin/snmpd -Dregister_mib -Dmib_init -L

To Check the Disk Space and Network on a Local or Remote Machine
# /usr/sfw/bin/snmpwalk -v1 -c public localhost HOST-RESOURCES-MIB::hrStorageIndex

# /usr/sfw/bin/snmpget -v1 -c public localhost HOST-RESOURCES-MIB::hrStorageSize.1

# /usr/sfw/bin/snmpwalk -v1 -c public localhost HOST-RESOURCES-MIB::hrStorageUsed

# /usr/sfw/bin/snmpnetstat -v 2c -c public -a localhost

if all these works, the sma is configured and brought on properly.

Conclusion:

You should now be able to provision the Solaris device within Traverse and receive all of the HOST-MIB applicable metrics (CPU, Disk). If an appropriate SNMPv3 account was created while completing the snmpconf wizard you will also have encrypted SNMP queries available to you at this point.