sentinel: don't announce-ip 0.0.0.0 when using hostname discovery#1750
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SAY-5 wants to merge 1 commit intoOT-CONTAINER-KIT:mainfrom
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sentinel: don't announce-ip 0.0.0.0 when using hostname discovery#1750SAY-5 wants to merge 1 commit intoOT-CONTAINER-KIT:mainfrom
SAY-5 wants to merge 1 commit intoOT-CONTAINER-KIT:mainfrom
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With announceHostnames=yes + resolveHostnames=yes the initContainer wrote `sentinel announce-ip <ip>` using whatever value the IP env variable held. The operator doesn't set IP on the Sentinel pod, so the CoalesceEnv default 0.0.0.0 ended up in sentinel.conf and Sentinels could not discover each other - hostname discovery was silently short-circuited (OT-CONTAINER-KIT#1748). Emit the announce-ip line only when we actually have a usable IP (i.e. the operator has set IP to something other than the ""/ 0.0.0.0 default), and rely on announce-hostnames + resolve-hostnames otherwise. When both hostname modes are on without a real IP, Redis Sentinel auto-discovers via DNS, which is exactly the intent of the feature. Signed-off-by: SAY-5 <SAY-5@users.noreply.github.com>
SAY-5
requested review from
drivebyer,
iamabhishek-dubey and
shubham-cmyk
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Summary
Fixes #1748.
With
announceHostnames=yes+resolveHostnames=yes, the initContainer wrotesentinel announce-ip <ip>using whatever value theIPenv variable held. The operator doesn't setIPon the Sentinel pod, soCoalesceEnv("IP", "0.0.0.0")returned the0.0.0.0default and that ended up insentinel.conf- Sentinels then broadcast0.0.0.0to peers and could not find each other, silently short-circuiting hostname discovery.Fix
Emit the
announce-ipline only when we actually have a usable IP (i.e. the operator has setIPto something other than""/0.0.0.0), and rely onannounce-hostnames+resolve-hostnamesotherwise. When both hostname modes are on without a real IP, Redis Sentinel auto-discovers via DNS, which is exactly the intent of the feature.Deployments that do set an IP explicitly (direct-IP mode or dual-stack configurations where
IPis propagated) keep the previous behaviour.Test plan
go build ./internal/agent/...announceHostnames=yes + resolveHostnames=yes + IP unset→ noannounce-ipline, hostname discovery worksannounceHostnames=yes + resolveHostnames=yes + IP=10.0.0.42→announce-ip 10.0.0.42line retainedannounceHostnames=no→ unchanged