Hello ;) I test check_snmp in local, with same OS. I have changed snmpd,cfg so i have: snmpget -v 1 -c public 192.168.0.2 .1.3.6.1.2.1.25.3.2.1.3.768 and NOT snmpget -v 1 -c public localhost .1.3.6.1.2.1.25.3.2.1.3.768 . Afer test correctly: snmpget -v 1 -c public 192.168.0.2 .1.3.6.1.2.1.25.3.2.1.3.768 HOST-RESOURCES-MIB::hrDeviceDescr.768 = STRING: GenuineIntel: Mobile Intel(R) Pentium(R) 4 - M CPU 2.20GHz by shell i insert this in webinterface of Nagios. I have modified checkcommands.cfg with this comand line: define command{ command_name check_snmp command_line $USER$/check_snmp -H $HOSTADDRESS$ -o $ARG1$ -C $ARG2$ } And services.cfg in this mode: # Service definition define service{ use generic-service ; Name of service template to use host_name novell1 service_description Info Processore - localhost is_volatile 0 check_period 24x7 max_check_attempts 1 normal_check_interval 1 retry_check_interval 1 contact_groups router-admins notification_interval 120 notification_period 24x7 notification_options w,u,c,r check_command check_snmp!.1.3.6.1.2.1.25.3.2.1.3.768!public } But in the webinterface check_snmp don't work: (Return code of 127 is out of bounds - plugin may be missing) Please why? Thanks a lot <hr size=1><a href="http://us.rd.yahoo.com/mail_it/taglines/*http://it.mail.yahoo.com">Yahoo! Mail</a>: gratis 1GB per i messaggi, antispam, antivirus, POP3