SNMP MIBs and Traps, and RMON Alarm Defaults
B-9
9664-A2-GB20-00 March 2000

Table B-6. linkUp and linkDown Variable-Bindings(1 of 2)

Interface Variable-Bindings Possible Cause

Physical Sublayer
Network ISDN S/T
(Supported by the
media-specific
RS232-like MIB.)
HifIndex (RFC 1573)
HifAdminStatus
(RFC 1573)
HifOperStatus (RFC 1573)
HdevLastTrapString
(devHealthAndStatus.-
mib)
HlinkDown – One or more alarm
conditions are active on the
interface.
The alarm condition for the
ISDN S/T interface is Loss of
Signal (LOS).
String:
‘$ifString $alarmString down.’
(e.g., ‘Network ISDN S/T
down due to LOS.’)
‘$ifString administratively
shutdown.’ (Due to an
intentional shutdown.)
HlinkUp – No alarms on the
interface.
String:
‘$ifString up.’
User Synchronous
Data Port
(Supported by the
media-specific
RS232-like MIB.)
HifIndex (RFC 1573)
HifAdminStatus
(RFC 1573)
HifOperStatus (RFC 1573)
HdevLastTrapString
(devHealthAndStatus.-
mib)
HlinkDown – One or more alarm
conditions are active on the
port.
Alarm conditions include:
DTR off1
RTS off1
‘’ – Not DTR or RTS, but
link is down.
String:
‘$ifString $alarmString down.’
(e.g., ‘Sync Data Port S01P1
DTR down.’)
‘$ifString administratively
shutdown.’ (Due to an
intentional shutdown.)
HlinkUp – No alarms on the
port.
String:
‘$ifString up.’
1This alarm condition only generates a linkUp/linkDown trap if the DTE supports
this lead state.