SNMP in AlphaCom XE

The AlphaCom XE runs a SNMP service, and supports SNMP polling and SNMP traps.

The main difference between a SNMP poll and a SNMP trap is which device initiates the communication. An SNMP poll is initiated by the SNMP server and the AlphaCom responds to the server. An SNMP trap is initiated by the AlphaCom when it has information to send (usually some event happened) and does not want to wait for the server to ask for information.

Stentofon MIB OID numbers

Zenitel Norway AS has assigned a Private Enterprise Number OID 26122.

The Zenitel Norway AS enterprise number is labeled enterprises.stentofon
Allocated Sub OIDs:

• 1 - enterprises.stentofon.alphacom
• 2 - enterprises.stentofon.ipstation

Note that the AlphaCom OID has of historical reasons not always followed the enterprise numbering defined above.

AlphaCom MIB

Revision 3

OID enterprises.26122: 
MIB text: AlphaCom MIB Revision 3

Revision 2

OID enterprises.26122: 
Included in RootFS versions: 0x-0xx and 1x-1xx (to be updated revision 2 released)
MIB text: AlphaCom MIB Revision 2

Revision 1

OID: enterprises.9362
Included in RootFS versions: 01-0x and 10-1x (to be updated revision 2 released)
MIB text: AlphaCom MIB Revision 1

SNMP polling

In addition to the AlphaCom MIB, the standard MIBs mibII, ucd-snmp and snmpv2 are implemented. These Mibs only implements polled information.

The AlphaCom MIB implements two main statuses:

AMC variables from the AlphaCom MIB:

Variable	Object ID	Comment
Nodestate	1.3.6.1.4.1.26122.1.1.1	AMC-IP status enabled/disabled. Shows if the AlphaCom is operational. Same info as in AlphaWeb, Node State - Operational
RTP Statistics	1.3.6.1.4.1.26122.1.2.1	RTP audio statistics

• AMC-IP status (Enabled/Disabled) (Same as AlphaWeb Node State/Operational)
• RTP statistics (Audio Statistics)

All MIBS variables are accessed through SNMP v2 protocol with community = public. All variables are read only. Example of reading the AlphaCom MIB with NET-SNMP:

> snmpwalk –v 2c –c public localhost enterprises.26122

The default MIBs are always active, but in order to receive polling requests from an SNMP server you need to open the firewall (Filters) in AlphaWeb (UDP port 161).

Define and enable UDP port 161 in Filters settings in AlphaWeb

SNMP variables

Linux variables:

Sensor	Comment
Ping	Ping response time
Network interface IO
Network interface eth0
Network interface eth1
IO trafic
Eth1 trafic
Uptime	Time since last reboot
CPU load
Disk free	Total free disk space
Disk free (opt/backup)	Free space for backup
Disk free (opt/nvram)	Free space for the nvram
Disk free (/tmp)
Memory: Physical memory
Memory: Swap space
Memory: Virtual memory
SNMP Linux load average
Active processes	The number of processes running in the Linux
Memory (Swap) Free
SNMP Linux meminfo
HTTP
ICMP Messages In
ICMP Messages Out
ICMP DestUnreachable In
ICMP DestUnreachable Out
ICMP Errors In
ICMP Errors Out
TCP Segments In
TCP Segments Out
SNMP Messages In
SNMP Messages Out
UDP Datagrams In
UDP Datagrams Out

SNMP Traps

The AlphaCom logs can be sent as SNMP traps.

The alert types that support SNMP traps have a number assigned to them, for example, 1001 is the number assigned to System Log events. The following table lists the number sent in the SNMP trap for each alert type.

Alert number	Object ID	Alert type	Alert criteria
1001	1.3.6.1.4.1.26122.1.11.1001	System log events	Station Line error Board down Device/MultiModule (card cage) error AGA/AE1 audio line error Software error Remote Control Input on/off Customized event logging (LOG command)
1002	1.3.6.1.4.1.26122.1.11.1002	Debug log events	Software debug information
1003	1.3.6.1.4.1.26122.1.11.1003	Call Statistics log events	Point to point calls Group Calls Call Request Ringing Group

SNMP trap is configured in AlphaWeb, System Configuration > Logging. Select destination ‘SNMP Trap’ and configure which logs you want to send.

Configuration of SNMP Traps in AlphaWeb

SNMP traps are using UDP port 162. As this is outbound data, there is no need to define this port in the Filers settings in AlphaWeb.

Frequently asked questions on SNMP

Where to get the MIB configuration file?

The active MIB file for an AMC-IP board can be found in the folder :

/usr/local/share/snmp/mibs/ALPHACOM-MIB.txt

MIB text: AlphaCom MIB Revision 3

How to change the SNMP UDP port number?

• Connect to the linux console through the ssh port using a terminal program like Putty.
• log in as normal with alpha/com
• In the linux bash write these commands:
  • su [enter]
  • root password [enter]
  • nano /usr/local/share/snmp/snmpd.conf

Add the line agentaddress 165 somewhere. Here 165 is the new portnumber used as an example:

• Use ctrl+X followed by Y to save and exit.

For more information see:
http://stackoverflow.com/questions/16205453/how-to-change-the-net-snmp-default-port-to-one-less-than-1024-in-linux
http://www.net-snmp.org/docs/man/snmpd.conf.html

How to change the SNMP trap UDP port number?

• Connect to the linux console through the ssh port using a terminal program like Putty.
• log in as normal with alpha/com
• In the linux bash write these commands:
  • su [enter]
  • root password [enter]
  • nano /var/opt/www/amc_ip_config.xml [enter]

Step a couple of pages down and you should find:

<destination>
        <type>snmptrap</type>
        
10.5.101.112
 

Add the new port number to the IP address like this: 10.5.101.112:165

• Use ctrl+X followed by Y to save and exit.
• Finally write:
  • /etc/init.d/syslog-ng restart

For more information see:
http://www.net-snmp.org/docs/man/snmpcmd.html

Related articles

• IP Station MIB