Prevent connections to replica on replica restart #57
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There is a brief period of time during a Redis replica restart when HAProxy can send writes to it; causing the following error: ``` READONLY You can't write against a read only replica. ``` This is because HAProxy (< 3.1.0) always treats newly detected backends as immediately UP - ready to serve traffic - UNTIL they failed their checks. HAProxy v3.1.0 adds the ability to configure a backend's initial state - init-state - and how/when it HAProxy determines that the backend is ready to receive traffic. This changes the HAProxy configuration so that a new Redis node is disqualified from client receiving traffic until HAProxy determines that the node is indeed a "master" node. This also updates the default operator's HAProxy image accordingly to receive the `init-state` HAProxy configuration option. References: - haproxy/haproxy#51 - haproxy/haproxy@50322df
indiebrain
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rurkss
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Dec 4, 2024
c-gerke
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indiebrain
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20241202--prevent-sending-writes-to-replicas-on-failover
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There is a brief period of time during a Redis replica restart when HAProxy can send writes to it; causing the following error:
This is because HAProxy (< 3.1.0) always treats newly detected backends as immediately UP - ready to serve traffic - UNTIL they failed their checks. HAProxy v3.1.0 adds the ability to configure a backend's initial state - init-state - and how/when it HAProxy determines that the backend is ready to receive traffic.
This changes the HAProxy configuration so that a new Redis node is disqualified from client receiving traffic until HAProxy determines that the node is indeed a "master" node.
This also updates the default operator's HAProxy image accordingly to receive the
init-stateHAProxy configuration option.References: