[vnetorch] missing handling of rx and tx interval of monitoring session

[zjswhhh]

What I did
Adding rx_monitor_timer and tx_monitor_timer handling per HLD: https://github.com/sonic-net/SONiC/blob/master/doc/vxlan/Overlay%20ECMP%20ehancements.md

sign-off: Jing Zhang [email protected]

Why I did it
It's needed for SSW HA scenario as DPU side bfd is a software solution, interval must be set to a reasonable value.

How I verified it
UTs.

Details if related

root@8486a8ef5a38:/# redis-cli -n 0  hgetall  "VNET_ROUTE_TUNNEL_TABLE:Vnet28:100.100.1.1/32"
 1) "endpoint"
 2) "9.1.0.1,9.1.0.2"
 3) "endpoint_monitor"
 4) "9.1.0.1,9.1.0.2"
 5) "profile"
 6) "Test_profile"
 7) "primary"
 8) "9.1.0.1"
 9) "adv_prefix"
10) "100.100.1.0/24"
11) "check_directly_connected"
12) "true"
13) "rx_monitor_timer"
14) "100"
15) "tx_monitor_timer"
16) "100"

root@8486a8ef5a38:/# redis-cli -n 0  hgetall  "BFD_SESSION_TABLE:default:default:9.1.0.1"    
 1) "local_addr"
 2) "9.9.9.9"
 3) "multihop"
 4) "true"
 5) "shutdown_bfd_during_tsa"
 6) "true"
 7) "rx_interval"
 8) "100"
 9) "tx_interval"
10) "100"

root@8486a8ef5a38:/# show bfd  sum
/bin/sh: 1: sudo: not found
Total number of BFD sessions: 1
Peer Addr    Interface    Vrf      State    Type          Local Addr      TX Interval    RX Interval    Multiplier  Multihop      Local Discriminator
-----------  -----------  -------  -------  ------------  ------------  -------------  -------------  ------------  ----------  ---------------------
9.1.0.1      default      default  Down     async_active  9.9.9.9                 100            100            10  true                            1
root@8486a8ef5a38:/# 

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[zjswhhh]

Hi @prsunny - can you help merge this? Without the request description change, orchagent will throw exception when we add rx_monitor_timer and tx_monitor_timer fields.

The code change should be covered by DVS UT.

[prsunny]

Please check backward compatibility.

[prsunny]

@zjswhhh , possible to fix UT coverage?

[prsunny]

@zjswhhh , would you also update the BFD hld with these changes?

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[Copilot]

Pull Request Overview

This PR adds support for configurable BFD monitoring intervals (rx_monitor_timer and tx_monitor_timer) for VNET tunnel routes, as specified in the Overlay ECMP enhancements HLD. This is needed for SSW HA scenarios where DPU-side BFD operates in software and requires reasonable interval values.

Key changes:

• Added rx_monitor_timer and tx_monitor_timer parameters to VNET route configuration
• Extended BFD session creation to accept and apply these timer values
• Added unit test coverage for the new timer functionality

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
tests/vnet_lib.py	Added rx_monitor_timer and tx_monitor_timer parameters to route creation/update helper functions
tests/test_vnet.py	Added new test case to verify timer handling in VNET routes with BFD monitoring
orchagent/vnetorch.h	Updated function signatures and request descriptor to support timer parameters
orchagent/vnetorch.cpp	Implemented timer handling throughout the route processing pipeline and BFD session creation

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[prsunny]

@zjswhhh , please fix conflicts

[mssonicbld]

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[zjswhhh]

Hi @prsunny - can you help merge please?

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