SNMP :- Simple Network Management Protocol.
SNMP is useful to figure out whats exactly happening from Device on Network.
SNMP is a agent which runs on Device and It will helps to monitor hardware/memory/CPU status in System . It will gather the information and sent to to management console .
port number for SNMP is 161.
[root@linuxtechnotes ~]# netstat -aunt
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:199 0.0.0.0:* LISTEN
tcp 0 0 192.168.150.129:54189 23.59.189.83:80 ESTABLISHED
tcp 1 1 192.168.150.129:54188 23.59.189.83:80 LAST_ACK
tcp 0 0 192.168.150.129:22 192.168.150.1:53360 ESTABLISHED
tcp 0 0 :::22 :::* LISTEN
tcp 0 0 ::1:631 :::* LISTEN
tcp 0 0 ::1:25 :::* LISTEN
udp 0 0 0.0.0.0:161 0.0.0.0:*
udp 0 0 0.0.0.0:68 0.0.0.0:*
udp 0 0 0.0.0.0:631 0.0.0.0:*
[root@linuxtechnotes ~]#
Configuration file :- /etc/snmp/snmpd.conf
what is the debug file for SNMP ?
for 5.x Linux servers its :- /etc/sysconfig/snmpd.options
For 6x :- /etc/sysconfig/snmpd
Below you can see default debug file for 6x Linux servers.
[root@linuxtechnotes ~]# cat /etc/sysconfig/snmpd
# snmpd command line options
# OPTIONS="-LS0-6d -Lf /dev/null -p /var/run/snmpd.pid"
[root@linuxtechnotes ~]#
Incase if you notice lot of udp connection in syslog and if you want to suppress, try to change the debug level to 5 and restart the snmpd deamon.
[root@linuxtechnotes ~]# cat /etc/sysconfig/snmpd
# snmpd command line options
OPTIONS="-LS0-5d -Lf /dev/null -p /var/run/snmpd.pid"
[root@linuxtechnotes ~]#
[root@linuxtechnotes ~]# service snmpd restart
Stopping snmpd: [ OK ]
Starting snmpd: [ OK ]
[root@linuxtechnotes ~]#
