def _perform_snmpwalk(snmp_config, check_plugin_name, base_oid, fetchoid):
# type: (SNMPHostConfig, CheckPluginName, OID, OID) -> SNMPRowInfo
added_oids = set([]) # type: Set[OID]
rowinfo = [] # type: SNMPRowInfo
for context_name in snmp_config.snmpv3_contexts_of(check_plugin_name):
rows = SNMPBackendFactory.walk(snmp_config,
oid=fetchoid,
check_plugin_name=check_plugin_name,
table_base_oid=base_oid,
context_name=context_name)
# I've seen a broken device (Mikrotik Router), that broke after an
# update to RouterOS v6.22. It would return 9 time the same OID when
# .1.3.6.1.2.1.1.1.0 was being walked. We try to detect these situations
# by removing any duplicate OID information
if len(rows) > 1 and rows[0][0] == rows[1][0]:
console.vverbose(
"Detected broken SNMP agent. Ignoring duplicate OID %s.\n" %
rows[0][0])
rows = rows[:1]
for row_oid, val in rows:
if row_oid in added_oids:
console.vverbose("Duplicate OID found: %s (%r)\n" %
(row_oid, val))
else:
rowinfo.append((row_oid, val))
added_oids.add(row_oid)
return rowinfo
def get_single_oid(snmp_config,
oid,
check_plugin_name=None,
do_snmp_scan=True):
# type: (SNMPHostConfig, str, Optional[str], bool) -> Optional[DecodedString]
# The OID can end with ".*". In that case we do a snmpgetnext and try to
# find an OID with the prefix in question. The *cache* is working including
# the X, however.
if oid[0] != '.':
if cmk.utils.debug.enabled():
raise MKGeneralException(
"OID definition '%s' does not begin with a '.'" % oid)
oid = '.' + oid
# TODO: Use generic cache mechanism
if snmp_cache.is_in_single_oid_cache(oid):
console.vverbose(" Using cached OID %s: " % oid)
cached_value = snmp_cache.get_oid_from_single_oid_cache(oid)
console.vverbose("%s%s%r%s\n" %
(tty.bold, tty.green, cached_value, tty.normal))
return cached_value
# get_single_oid() can only return a single value. When SNMPv3 is used with multiple
# SNMP contexts, all contextes will be queried until the first answer is received.
if check_plugin_name is not None and snmp_config.is_snmpv3_host:
snmp_contexts = _snmpv3_contexts_of(snmp_config, check_plugin_name)
else:
snmp_contexts = [None]
console.vverbose(" Getting OID %s: " % oid)
for context_name in snmp_contexts:
try:
value = SNMPBackendFactory.get(snmp_config,
use_cache=_enforce_stored_walks,
oid=oid,
context_name=context_name)
if value is not None:
break # Use first received answer in case of multiple contextes
except Exception:
if cmk.utils.debug.enabled():
raise
value = None
if value is not None:
console.vverbose("%s%s%r%s\n" %
(tty.bold, tty.green, value, tty.normal))
else:
console.vverbose("failed.\n")
if value is not None:
decoded_value = convert_to_unicode(
value, encoding=snmp_config.character_encoding
) # type: Optional[DecodedString]
else:
decoded_value = value
snmp_cache.set_single_oid_cache(oid, decoded_value)
return decoded_value
def walk_for_export(snmp_config, oid):
# type: (SNMPHostConfig, OID) -> SNMPRowInfoForStoredWalk
rows = SNMPBackendFactory.walk(snmp_config, use_cache=False, oid=oid)
return _convert_rows_for_stored_walk(rows)