Access HostConfig Data cmk.agent_based.v2 SNMP CheckPlugin

LouisBehrmann · August 3, 2026, 8:33am

Hello,

i am trying to develope a plugin that is intended to sanitize our checkmk hostconfiguration by comparing:

Hostname to SNMP Hostname (.1.3.6.1.2.1.1.5)
Host address to DNS A-Record
Hostname to DNS PTR-Record

i am able to obtain the SNMP Hostname by following the article: Developing SNMP-based check plug-ins .

How do i gain access to the hostname and IP-Adress of the host?

r.sander · August 3, 2026, 9:22am

I have code in my check_snmp extension that does a similar thing:

github.com/HeinleinSupport/check_mk_extensions

check_snmp/server_side_calls/check_snmp.py

cmk2.5


      
              hostname = params['hostname']
          else:
              hostname = "$HOSTADDRESS$"
          hostname = replace_macros(hostname, host_config.macros)
          
          args = ["-H", hostname]
          
          if 'creds' in params:
              args += _creds_to_args(params['creds'])
          else:
              loading_result = config.load(
                  discovery_rulesets=(), get_builtin_host_labels=lambda x: {}
              )
              config_cache = loading_result.config_cache
              ip_lookup_config = config_cache.ip_lookup_config()
              host_name = HostName(host_config.name)
              ip_family = ip_lookup_config.default_address_family(host_name)
              ip_address = HostAddress(host_config.primary_ip_config.address)
              snmp_config = config_cache.make_snmp_config(host_name, ip_family, ip_address, SourceType.HOST, backend_override=None)
              args += _creds_to_args(snmp_config.credentials)