Chapter 11
Configuring Advanced BGP
S e n d d o c u m e n t c o m m e n t s t o n e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m .
ISSU
Cisco NX-OS supports in-service software upgrades (ISSU). ISSU allows you to upgrade software
without impacting forwarding.
The following conditions are required to support ISSU:
•
•
If either of these requirements is not met, Cisco NX-OS issues a warning. You can proceed with the
upgrade or downgrade, but service might be disrupted.
Note
Cisco NX-OS cannot guarantee ISSU for non-default timer values if the negotiated hold time between
BGP peers is less than the system switchover time.
In Cisco NX-OS Release 4.2(3) or later, if the negotiated hold time is less than the system switchover
time, you can optionally proceed with an upgrade that may be distruptive. In earlier releases, you must
reconfigure the hold timers on the BGP peers to be greater than the system switchover time and restart
the BGP sessions before you can proceed with the ISSU.
Virtualization Support
Cisco NX-OS supports multiple instances of BGP that run on the same system. BGP supports Virtual
Routing and Forwarding instances (VRFs) that exist within virtual device contexts (VDCs). You can
configure one BGP instance in a VDC, but you can have multiple VDCs on the system.
By default, Cisco NX-OS places you in the default VDC and default VRF unless you specifically
configure another VDC and VRF. See the Cisco NX-OS Virtual Device Context Configuration Guide and
Chapter 14, "Configuring Layer 3 Virtualization."
Licensing Requirements for Advanced BGP
The following table shows the licensing requirements for this feature:
OL-20002-02
Graceful restart must be enabled (default)
Keepalive and hold timers must not be smaller than their default values
Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x
Licensing Requirements for Advanced BGP
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