SNMP Setup

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SNMP in StarOS[edit]

V2[edit]

As of StarOS 2.11, SNMP data is available to provide default interface information, including system uptime and traffic across system interfaces. The V2 SNMP Agent does not support changing the community string from the default of public.

V3 1.1.x release series[edit]

For builds up to and including 1.1.13, a memory leak exists within the SNMP agent that makes it strongly recommended to disable the SNMP agent. Beginning with 1.1.14, the 1.1.x series of drivers for StarV3 support default SNMP v1/2 interface information including system uptime, traffic across the loopback and ethernet interfaces, and any bridge interfaces in use. The 1.1.14 version of the SNMP agent does not provide any information about traffic across a wireless interface.

V3 1.3.x release series[edit]

In 1.3.0 and subsequent releases, there is a fully functional SNMP v1/2 agent that includes interface information including system uptime and traffic across the loopback, ethernet, wifi, and wpci interfaces as well as any bridge groups. In addition, the 1.3.x series includes experimental MIBs that provide information about wireless cards installed in the system as well as association lists for those cards. In order to receive the full experimental MIB information, your SNMP monitoring software must use SNMPv2.

Configuring SNMP[edit]

SNMP can be enabled by logging into a StarOS unit via an SSH client, such as PuTTY. Within the SSH interface, select the system menu and the services sub-menu. In StarV3, the fourth option on this menu is the menu for the SNMP agent, which has two choices.

The first choice, "configure service", allows you to choose whether the service should be enabled on system startup and to configure the community string. By default, this community string is "public".

The second choice, "service activation", allows you to start, restart, or stop the SNMP agent. If you are enabling SNMP for the first time, you must either use service activation to start the service or reboot the system after enabling SNMP. Using service activation is preferred as it takes only a few seconds to start the service and will not take the device offline for a reboot.

Experimental MIBs[edit]

Wireless Card Information[edit]

As of 1.3.11 build 2717, the following OIDs are available in the experimental MIB for wireless cards.

Object Name Description OID SNMP versions First available
vnCardIfName Wireless card interface name (e.g. wpci0) .1.3.6.1.3.16313.1.25.2.1.1.1 v1, v2 v1.3.0 (b.2446)
vnCardMacAddress MAC address of wireless card .1.3.6.1.3.16313.1.25.2.1.1.2 v1, v2 v1.3.0 (b.2446)
vnCardAssocCount Number of associations .1.3.6.1.3.16313.1.25.2.1.1.3 v1, v2 v1.3.0 (b.2446)
vnCardSignalQuality Signal quality of wireless card
Displayed in percent (100% is best)
.1.3.6.1.3.16313.1.25.2.1.1.4 v1, v2 v1.3.0 (b.2446)
vnCardSignalLevel Signal level of wireless card
Displayed in dBm
.1.3.6.1.3.16313.1.25.2.1.1.5 v1, v2 v1.3.0 (b.2446)
vnCardSignalNoise Signal noise of wireless card
Displayed in dBm
.1.3.6.1.3.16313.1.25.2.1.1.6 v1, v2 v1.3.0 (b.2446)
vnCardOperatingFreq Operating frequency of wireless card
Displayed in MHz
.1.3.6.1.3.16313.1.25.2.1.1.7 v1, v2 v1.3.10 (b.2716)

NOTE: For systems running firmware versions prior to build 2639 (versions 1.3.0 to 1.3.5), the signal noise for wireless cards will always return -95 dBm. Beginning with build 2639 (version 1.3.6), the Atheros BlackMagic(TM) method for noise calculation was implemented and SNMP information reports more accurate noise information.

NOTE: For systems running firmware versions in the 1.4.x series, the Quality for wireless cards operating in Access Point mode will always report 0. In addition, the signal level and signal noise for these cards will always report -95 dBm. More information is available here: http://forums.star-os.com/showpost.php?p=68979&postcount=29.

Wireless interfaces are indexed such that wpci1 is 1000, wpci2 is 1100, and so forth. Thus, the wireless card interface name (vnCardIfName) for wpci1 is available at .1.3.6.1.3.16313.1.25.2.1.1.1.1000

Association List[edit]

In addition to the wireless interface information, it is possible in build 2446 and later to query association information for clients on the wireless interfaces. The following OIDs are currently available:

Object Name Description OID SNMP versions
vnAssocMacAddress MAC Address of associated client .1.3.6.1.3.16313.1.25.2.2.1.1 v1, v2
vnAssocSignalQuality Signal quality of associated client
Displayed in percent (100% is best)
.1.3.6.1.3.16313.1.25.2.2.1.2 v1, v2
vnAssocSignalLevel Signal level of associated client
Displayed in dBm
.1.3.6.1.3.16313.1.25.2.2.1.3 v1, v2
vnAssocSignalNoise Signal noise of associated client
Displayed in dBm
.1.3.6.1.3.16313.1.25.2.2.1.4 v1, v2
vnAssocAid Association ID of client .1.3.6.1.3.16313.1.25.2.2.1.5 v1, v2
vnAssocIdleTime Inactivity time of client
Displayed in seconds
.1.3.6.1.3.16313.1.25.2.2.1.6 v1, v2
vnAssocIpAddress Client's last known IP address .1.3.6.1.3.16313.1.25.2.2.1.7 v1, v2
vnAssocTxPower Client's transmit power
Displayed in dBm (0..30)
.1.3.6.1.3.16313.1.25.2.2.1.8 v1, v2
vnAssocRxRate Client's receive rate .1.3.6.1.3.16313.1.25.2.2.1.9 v1, v2
vnAssocTxRate Client's transmit rate .1.3.6.1.3.16313.1.25.2.2.1.10 v1, v2
vnAssocRxBytes Bytes recieved from client
Counter of traffic from client to AP
.1.3.6.1.3.16313.1.25.2.2.1.20 v2 only
vnAssocRxBytesPerSecond Client's current rx traffic per second
Displayed in bytes
.1.3.6.1.3.16313.1.25.2.2.1.21 v1, v2
vnAssocTxBytes Bytes transmitted to client
Counter of traffic from AP to client
.1.3.6.1.3.16313.1.25.2.2.1.22 v2 only
vnAssocTxBytesPerSecond Client's current tx traffic per second
Displayed in bytes
.1.3.6.1.3.16313.1.25.2.2.1.23 v1, v2

NOTE: For systems running firmware versions prior to build 2639 (versions 1.3.0 to 1.3.5), the signal noise for wireless cards will always return -95 dBm. Beginning with build 2639 (version 1.3.6), the Atheros BlackMagic method for noise calculation was implemented and SNMP information reports more accurate noise information

NOTE: For systems running firmware versions in the 1.5.16.x series with 802.11n radios, the Client receive & transmit rates in the association list SNMP tables are not properly reported. The numbers reported appear to be random. This is still unresolved as of 1.5.17


Associated clients are indexed by which wireless interface they are associated to and their association aid. The portion of the index based on the wireless interface will have the same SNMP index value as the wireless card the client is associated to. Thus, clients associated to wpci1 will have their MAC Address available at .1.3.6.1.3.16313.1.25.2.2.1.1.1000.X, where X is the vnAssocAid for that client. These indexes are dependent upon the order in which clients have associated to the access point and are thus not statically defined. This lack of a static interface causes monitoring programs such as Cacti to have difficulty graphing information based on these OIDs.