RSVP-TE Overview

The configuration for RSVP-TE is split into two parts:

Core Prerequisites and Global Configuration

For RSVP-TE to function correctly, several global and interface-level settings must be configured:

IP Routing: IP Routing must be enabled globally on the switch.
MPLS Enablement: MPLS must be enabled globally on the switch.
Traffic Engineering: Traffic-engineering must be enabled globally on the switch.
Router ID: A router ID must be configured in either the traffic-engineering configuration or the general routing configuration.
IGP Traffic Engineering: Traffic engineering must be active within the Interior Gateway Protocol (IGP), such as IS-IS or OSPF.
Interface Traffic Engineering: Traffic-engineering must be enabled on interfaces that use RSVP-TE.
Source Interface: A local interface, typically a Loopback interface, is required to derive the source IP address for tunnels.
Protocol Activation: RSVP is globally activated using the no shutdown command within the MPLS RSVP configuration submode.

Arista RSVP-TE supports various router roles, with performance capabilities validated through internal testing.

Table 1. Supported Scalability
Role	Description	Scale Highlights
RSVP-TE P2P LSPs	The maximum number of RSVP-TE P2P LSPs Arista supports in any role.	30k LSPs
RSVP-TE P2P Tunnels	The maximum number of RSVP-TE P2P Tunnels Arista supports on a headend.	2k (1k with hot-standby secondary)
RSVP-TE P2MP Sub-LSPs	The maximum number of RSVP-TE P2MP sub-LSPs Arista supports in any role.	10k sub-LSPs
RSVP-TE P2MP Tunnels	The maximum number of RSVP-TE P2MP tunnels Arista supports on a headend.	Up to 60 MVPN tunnels with up to 64 leaves each

Only IPv4 is supported.
Only the default VRF is supported.
Only strict EROs with host hops (/32) are supported.
TE links with secondary IP addresses are not supported.
Subinterface links are not supported.
Changing the RSVP FRR mode while a bypass tunnel is already in use could cause both the primary and bypass tunnels to go down, resulting in traffic loss.
Changing the RSVP SRLG mode while a bypass tunnel is already in use could cause both the primary and bypass tunnels to go down, resulting in traffic loss.
The maximum number of IS-IS/ospfv2 routers supported by CSPF on a single broadcast network is 30.
The maximum number of IS-IS/ospfv2 adjacencies supported by CSPF for a single router is 500.
The maximum number of hops supported for an RSVP LSP is 256.
CSPF considers a maximum of 16 SRLGs per TE link when excluding SRLGs during path computation.
Explicit-null label termination does not work on 7500R and 7280R/7280R2 platforms when additional labels (such as VPN labels) are present on the MPLS packet.

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