Type of access node identifier that is used to fill
in the circuit ID suboption of option 82 when the value
of hh3cDhcpSnoop2IfOption82CIDMode is set to 'verbose'.
The SET operation of this object must be with the SET
operation of hh3cDhcpSnoop2IfOpt82CIDMode.
'invalid' indicates that the node identifier is NOT used
to fill in the circuit ID suboption of option 82.
If the value of hh3cDhcpSnoop2IfOpt82CIDMode is NOT
'verbose', the value of this object is set to 'invalid'
automatically.
Otherwise the value of this object cannot be set to 'invalid'.
'mac' indicates that the node identifier is
filled in with the bridge MAC of DHCP snooping device.
If the value of hh3cDhcpSnoop2IfOpt82CIDMode is set to
'verbose', the default value of this object is 'mac'.
'sysname' indicates that the node identifier
is filled in with the sysname of the DHCP snooping.
'userDefine' indicates the node identifier
is filled in with the string defined by the object
of hh3cDhcpSnoop2IfOpt82CIDNodeStr.
If the value is set to 'userDefine', the value of
hh3cDhcpSnoop2IfOpt82CIDNodeStr must also be set to
a non-zero length string.