I am trying to find the best way to show available line speed in a router or firewall. I am trying to use the plugin with a pix 501 for testing. When I run

"perl -H {pix ip} -C {my community string} -n {interface name} -f -S

I receive the following information

Use of uninitialized value $speed_real in concatenation (.) or string at line 797
inside interface:UP:1 UP: OK | inside interface_in_octet=80955475c inside interface_out_octet=20367859c inside interface_speed_bps=

My question is why does interface_speed_bps show as blank. Just the equals sign then nothing. Is the error message relevant or am I doing something wrong? Please let me know if I am leaving out important information as I am pretty new to nagios and snmp. Thanks in advance for any help!