{"record":{"id":"cf1ff6b361781073","repo":"kubernetes/kops","slug":"error-generating-rsa-private-key-v","errorCode":null,"errorMessage":"error generating RSA private key: %v","messagePattern":"error generating RSA private key: (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"pkg/pki/privatekey.go","lineNumber":68,"sourceCode":"\treturn &PrivateKey{Key: k}, nil\n}\n\nfunc GeneratePrivateKey() (*PrivateKey, error) {\n\trsaKeySize := DefaultPrivateKeySize\n\n\tif os.Getenv(\"KOPS_RSA_PRIVATE_KEY_SIZE\") != \"\" {\n\t\ts := os.Getenv(\"KOPS_RSA_PRIVATE_KEY_SIZE\")\n\t\tif v, err := strconv.Atoi(s); err != nil {\n\t\t\treturn nil, fmt.Errorf(\"error parsing KOPS_RSA_PRIVATE_KEY_SIZE=%s as integer\", s)\n\t\t} else {\n\t\t\trsaKeySize = int(v)\n\t\t\tklog.V(4).Infof(\"Generating key of size %d, set by KOPS_RSA_PRIVATE_KEY_SIZE env var\", rsaKeySize)\n\t\t}\n\t}\n\n\trsaKey, err := rsa.GenerateKey(crypto_rand.Reader, rsaKeySize)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"error generating RSA private key: %v\", err)\n\t}\n\n\tprivateKey := &PrivateKey{Key: rsaKey}\n\treturn privateKey, nil\n}\n\ntype PrivateKey struct {\n\tKey crypto.Signer\n}\n\nfunc (k *PrivateKey) AsString() (string, error) {\n\t// Nicer behaviour because this is called from templates\n\tif k == nil {\n\t\treturn \"\", fmt.Errorf(\"AsString called on nil private key\")\n\t}\n\n\tvar data bytes.Buffer\n\t_, err := k.WriteTo(&data)","sourceCodeStart":50,"sourceCodeEnd":86,"githubUrl":"https://github.com/kubernetes/kops/blob/4c8573c808a73d578c5eadc86d410646ea0b0d73/pkg/pki/privatekey.go#L50-L86","documentation":"rsa.GenerateKey failed while creating the RSA private key of the configured size. Go returns an error here only on entropy/rand reader failure (rare) or resource constraints; kOps wraps and propagates it.","triggerScenarios":"Any call path into GeneratePrivateKey (createKeypair, IssueCert, BuildChallengeServerCertificate, Run) where crypto/rand reads fail — e.g. exhausted entropy, extremely large KOPS_RSA_PRIVATE_KEY_SIZE values causing timeout/OOM in constrained environments.","commonSituations":"Containers/virtual machines with depleted entropy pools, setting KOPS_RSA_PRIVATE_KEY_SIZE very high (e.g. 16384) on small nodes causing long generation or memory pressure.","solutions":["Retry the operation; entropy failures are typically transient.","Check /dev/urandom availability and host entropy (or ensure getrandom works) in the container.","Reduce KOPS_RSA_PRIVATE_KEY_SIZE to 2048 or 4096 if an extreme size was requested.","Verify node memory/CPU is sufficient for the requested key size."],"exampleFix":null,"handlingStrategy":"retry","validationCode":"if s := os.Getenv(\"KOPS_RSA_PRIVATE_KEY_SIZE\"); s != \"\" {\n    if v, err := strconv.Atoi(s); err == nil && v > 8192 {\n        return fmt.Errorf(\"key size %d likely too large for this host\", v)\n    }\n}","typeGuard":null,"tryCatchPattern":"key, err := pki.GeneratePrivateKey()\nif err != nil {\n    if strings.Contains(err.Error(), \"generating RSA private key\") {\n        time.Sleep(time.Second)\n        key, err = pki.GeneratePrivateKey() // one retry\n    }\n    if err != nil { return err }\n}","preventionTips":["Ensure /dev/urandom and getrandom work in containers","Keep KOPS_RSA_PRIVATE_KEY_SIZE at 2048-4096","Retry transient entropy failures before failing the task"],"tags":["pki","rsa","crypto","entropy"],"backgroundTag":"rsa-key-generation-failed","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"}