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Disabling BGP to establish a session to a peer or peer group
This task enables you to temporarily tear down the BGP session to a specific peer or peer group so that
you can perform network upgrade and maintenance without needing to delete and reconfigure the peer
or peer group. To recover the session, execute the
undo peer ignore
command.
To disable BGP to establish a session to a peer or peer group (IPv4 unicast/multicast address family):
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter BGP view or BGP-VPN
instance view.
•
Enter BGP view:
bgp
as-number
•
Enter BGP-VPN instance view:
a.
bgp
as-number
b.
ip vpn-instance
vpn-instance-name
N/A
3.
Disable BGP to establish a
session to a peer or peer
group.
peer
{
group-name
|
ip-address
}
ignore
By default, BGP can establish a
session to a peer or peer group.
To disable BGP to establish a session to a peer or peer group (IPv6 unicast/multicast address family):
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter BGP view or BGP-VPN
instance view.
•
Enter BGP view:
bgp
as-number
•
Enter BGP-VPN instance view:
a.
bgp
as-number
b.
ip vpn-instance
vpn-instance-name
N/A
3.
Disable BGP to establish a
session to a peer or peer
group.
peer
{
group-name
|
ipv6-address
}
ignore
By default, BGP can establish a
session to a peer.
Configuring GTSM for BGP
IMPORTANT:
•
When GTSM is configured, the local device can establish an EBGP session with the peer after both
devices pass GTSM check, regardless of whether the maximum number of hops is reached.
•
To use GTSM, you must configure GTSM on both the local and peer devices. You can specify different
hop-count
values for them.
The Generalized TTL Security Mechanism (GTSM) protects a BGP session by comparing the TTL value in
the IP header of incoming BGP packets against a valid TTL range. If the TTL value is within the valid TTL
range, the packet is accepted. If not, the packet is discarded.
The valid TTL range is from 255 – the configured hop count
+ 1 to 255.
