{"record":{"id":"51b298604eba9726","repo":"kubernetes/kops","slug":"failed-to-consistently-write-file-q-too-many-re","errorCode":null,"errorMessage":"failed to consistently write file %q - too many retries","messagePattern":"failed to consistently write file %q - too many retries","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"pkg/dns/hosts/hosts.go","lineNumber":213,"sourceCode":"\t\treturn fmt.Errorf(\"error writing file %q: %v\", p, err)\n\t}\n\n\treturn nil\n}\n\n// Because we are bind-mounting /etc/hosts, we can't do a normal\n// atomic file write (where we write a temp file and rename it);\n// instead we write the file, pause, re-read and see if anyone else\n// wrote in the meantime; if so we rewrite again.  By pausing for a\n// random amount of time, eventually we'll win the write race and\n// exit.  This doesn't guarantee fairness, but it should mean that the\n// end-result is not malformed (i.e. partial writes).\nfunc pseudoAtomicWrite(p string, b []byte, mode os.FileMode) error {\n\tattempt := 0\n\tfor {\n\t\tattempt++\n\t\tif attempt > 10 {\n\t\t\treturn fmt.Errorf(\"failed to consistently write file %q - too many retries\", p)\n\t\t}\n\n\t\tif err := os.WriteFile(p, b, mode); err != nil {\n\t\t\tklog.Warningf(\"error writing file %q: %v\", p, err)\n\t\t\tcontinue\n\t\t}\n\n\t\tn := 1 + math_rand.Intn(20)\n\t\ttime.Sleep(time.Duration(n) * time.Millisecond)\n\n\t\tcontents, err := os.ReadFile(p)\n\t\tif err != nil {\n\t\t\tklog.Warningf(\"error re-reading file %q: %v\", p, err)\n\t\t\tcontinue\n\t\t}\n\n\t\tif bytes.Equal(contents, b) {\n\t\t\treturn nil","sourceCodeStart":195,"sourceCodeEnd":231,"githubUrl":"https://github.com/kubernetes/kops/blob/4c8573c808a73d578c5eadc86d410646ea0b0d73/pkg/dns/hosts/hosts.go#L195-L231","documentation":"The pseudo-atomic writer exhausted its retry budget: every write to /etc/hosts was overwritten by another process before the verification re-read, so the guarded block could never be committed consistently.","triggerScenarios":"Thrown at pkg/dns/hosts/hosts.go:213 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["Identify the competing writer (other containers or system daemons writing /etc/hosts) and serialize updates","Retry at a quieter moment; the random-backoff loop wins eventually","Reduce concurrent processes mutating hosts entries on the node"],"exampleFix":null,"handlingStrategy":"retry","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"4c8573c808a73d578c5eadc86d410646ea0b0d73","analyzedAt":"2026-09-05T04:13:19.212Z","contentChangedAt":"2026-09-05T04:13:19.212Z","schemaVersion":2},"datasetVersion":"2026-09-12T07:17:12.445Z"}