hold-time (Protocols BGP)
Syntax
hold-time seconds;
Hierarchy Level
[edit logical-systems logical-system-name protocols bgp], [edit logical-systems logical-system-name protocols bgp group group-name], [edit logical-systems logical-system-name protocols bgp group group-name neighbor address], [edit logical-systems logical-system-name routing-instances routing-instance-name protocols bgp], [edit logical-systems logical-system-name routing-instances routing-instance-name protocols bgp group group-name], [edit logical-systems logical-system-name routing-instances routing-instance-name protocols bgp group group-name neighbor address], [edit protocols bgp], [edit protocols bgp group group-name], [edit protocols bgp group group-name neighbor address], [edit routing-instances routing-instance-name protocols bgp], [edit routing-instances routing-instance-name protocols bgp group group-name], [edit routing-instances routing-instance-name protocols bgp group group-name neighbor address]
Description
Specify the hold-time value to use when negotiating a connection with the peer. The hold-time value is advertised in open packets and indicates to the peer the length of time that it should consider the sender valid. If the peer does not receive a keepalive, update, or notification message within the specified hold time, the BGP connection to the peer is closed and routing devices through that peer become unavailable.
The hold time is three times the interval at which keepalive messages are sent.
BGP on the local routing device uses the smaller of either the local hold-time value or the peer’s hold-time value received in the open message as the hold time for the BGP connection between the two peers.
Starting in Junos OS Release 12.3, the BGP hold-time value can be zero (0). This implies that the speaker does not expect keepalive messages from its peer to maintain the BGP session. When negotiating between two peers, if one side requests a nonzero hold time and the other requests a zero hold time, the negotiation settles on the nonzero value and keepalive intervals are determined accordingly. Both sides must be set to zero for keepalive messages to stop being sent.
Options
seconds—Hold
time.
Range: 3 through 65,535 seconds (or 0 for infinite hold time)
Range: 10 through 65,535 seconds for EX Series switches.
Default: 90 seconds
When you set a hold-time value of 3 through 19 seconds,
we recommend that you also configure the BGP precision-timers statement. The precision-timers statement ensures that
if scheduler slip messages occur, the routing device continues to
send keepalive messages. When the precision-timers statement
is included, keepalive message generation is performed in a dedicated
kernel thread, which helps to prevent BGP session flaps.
Starting in Junos OS Release 17.3R1, the precision-timers statement is supported on QFX Series switches.
Required Privilege Level
routing—To view this statement in the configuration.
routing-control—To add this statement to the configuration.
Release Information
Statement introduced before Junos OS Release 7.4.