Revise backend pool names and add second backend pool #127786
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In this scenario, 2nd backend pool is needed, as in current scenario, both backend VMs respond to both frontend IPs. This effectively breaks DHCP relay HA scenario, as requests to both Frontend Addresses may go to the same backend server, breaking HA provided by Load Balancer. Also, taking into consideration that source port of DHCP RElay is always 67, load balancing will not work as you would expece for ordinary connections (both Src IP and Port, and DST IP And port are always the same), this means connections will stick to some servers. In situation, where DHCP Servers on VMs may be also configured in HA LB mode, this can fully break DHCP functionality.
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Pull Request Overview
This PR addresses a critical DHCP relay high availability issue where both backend VMs were responding to both frontend IPs, breaking the HA scenario. The changes introduce a second backend pool to ensure proper traffic distribution and prevent DHCP functionality issues caused by sticky connections.
Key changes:
- Renamed the original backend pool from
backend-pooltobackend-pool-1for consistency - Added a second backend pool (
backend-pool-2) with configuration instructions - Updated load balancer rules to reference the appropriate backend pools
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Co-authored-by: Copilot <[email protected]>
Co-authored-by: Copilot <[email protected]>
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Learn Build status updates of commit b896e57: ✅ Validation status: passed
For more details, please refer to the build report. |
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Learn Build status updates of commit c98077e: ✅ Validation status: passed
For more details, please refer to the build report. |
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In this scenario, 2nd backend pool is needed, as in current scenario, both backend VMs respond to both frontend IPs. This effectively breaks DHCP relay HA scenario, as requests to both Frontend Addresses may go to the same backend server, breaking HA provided by Load Balancer. Also, taking into consideration that source port of DHCP RElay is always 67, load balancing will not work as you would expece for ordinary connections (both Src IP and Port, and DST IP And port are always the same), this means connections will stick to some servers. In situation, where DHCP Servers on VMs may be also configured in HA LB mode, this can fully break DHCP functionality.
VMs LB template that included into this document also needs reviewing or adding here as static text.