R0106-HP MSR Router Series Layer 3 - IP Routing Command Reference(V7)
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Syntax
balance [ ebgp | eibgp | ibgp ] number
undo balance [ ebgp | eibgp | ibgp ]
Default
Load balancing is not enabled.
Views
BGP IPv4 unicast address family view, BGP-VPN IPv4 unicast address family view, BGP IPv6 unicast
address family view, BGP-VPN IPv6 unicast address family view, BGP IPv4 multicast address family view,
BGP IPv6 multicast address family view
Predefined user roles
network-admin
Parameters
ebgp: Enables load balancing over EBGP routes.
eibgp: Enables load balancing between EBGP and IBGP routes.
ibgp: Enables load balancing over IBGP routes.
number: Specifies the maximum number of BGP ECMP routes for load balancing, in the range of 1 to 32.
When it is set to 1, load balancing is disabled.
Usage guidelines
Unlike IGP, BGP has no explicit metric for making load balancing decision. Instead, it implements load
balancing by modifying route selection rules. If multiple BGP routes destined for a network meet the
following conditions, the device selects the specified number of routes for load balancing:
• The routes have the same AS_PATH, ORIGIN, LOCAL_PREF, and MED attributes.
• All the routes are reflected by a route reflector, or none of the routes is reflected by a route reflector.
If you do not provide the ibgp, eibgp, or ebgp keyword, this command enables load balancing over
EBGP routes and IBGP routes, but not between EBGP and IBGP routes.
After you execute the balance eibgp number command, the balance [ ebgp | ibgp ] number and undo
balance [ ebgp | ibgp ] commands cannot be executed; and vice versa.
Examples
# In BGP IPv4 unicast address family view, enable load balancing and specify the maximum number of
BGP ECMP routes used for load balancing as 2.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] address-family ipv4 unicast
[Sysname-bgp-ipv4] balance 2
# In BGP-VPN IPv6 unicast address family view, enable load balancing and specify the maximum
number of BGP ECMP routes for load balancing as 2.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] ip vpn-instance vpn1
[Sysname-bgp-vpn1] address-family ipv6 unicast
[Sysname-bgp-ipv6-vpn1] balance 2