SNMP introduction

--chris----chris-- Member Posts: 1,518 ■■■■■□□□□□
I recently started to learn SNMP (via Zabbix), and I have a question. I know the terms pretty well since there are only 6 or so key terms, but I am left scratching my head about how the SNMP agent is implemented.

Is the agent preloaded on the device that has SNMP support? That would mean I need to access the devices interface to enable the SNMP agent correct? Or am i going down the wrong path here?

I gathered that from the agent explanation here:
http://www.manageengine.com/network-monitoring/what-is-snmp.html#snmp-agent


Im sure I will have plenty of other questions, this will just be the start....

Comments

  • TechGuy215TechGuy215 Member Posts: 404 ■■■■□□□□□□
    I'm pretty sure that any device that has an SNMP agent, has a service that autodiscovers. Meaning, by default SNMP on said device is turned on, listening, and ready to accept request.
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  • networker050184networker050184 Mod Posts: 11,962 Mod
    That is not true. It would be a pretty big security risk to have things open and responding to SNMP by default. Every device I've worked with it has to be enabled manually.
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  • phoeneousphoeneous Member Posts: 2,333 ■■■■■■■□□□
    That is not true. It would be a pretty big security risk to have things open and responding to SNMP by default. Every device I've worked with it has to be enabled manually.

    Most printers have snmp enabled by default.

    --chris--, I've been using zabbix for quite some time so feel free to ask me anything. To answer your question, depends on what you want to monitor. For networking devices like firewalls, routers, and switches, you have to enable snmp and tell it the address of the snmp host. For windows boxes, you'll need to install the zabbix agent and specify the community in the windows snmp service and allow it through the windows firewall if you use it.
  • DevilWAHDevilWAH Member Posts: 2,997 ■■■■■■■■□□
    TechGuy215 wrote: »
    I'm pretty sure that any device that has an SNMP agent, has a service that autodiscovers. Meaning, by default SNMP on said device is turned on, listening, and ready to accept request.

    I have to agree, while not all, there is a scary number of devices from big manufactures that have snmp rw and ro set to public and private strings and running as default! Its getting better but one of the first things i check on a new device.

    on or not by defualt your going to have to connect and configure it on each agent. (lots of tools to automate this on larger installs)
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  • CodeBloxCodeBlox Member Posts: 1,363 ■■■■□□□□□□
    I'd have to say I've come across more devices with it off by default however most have default community strings of public... That becomes the bigger problem when lazy admins have enabled SNMP and left the device with the default string.
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  • --chris----chris-- Member Posts: 1,518 ■■■■■□□□□□
    Thank you everyone for your responses, its been a big help. Ill spend some time today attempting to connect the Zabbix host to a device with the agent installed. If I run into any trouble I will be sure to get a hold of you phoeneous.

    edit: Forgot to mention, this stuff is awesome.

    edit2: Found this Cisco tutorial on SNMP, very good read for someone like me:
    http://www.cisco.com/networkers/nw04/presos/docs/NMS-1N02.pdf
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