elastic/elasticsearch · error · UserException

78

78

Error message

encountered [%d] error%s parsing [%s]%s[%d]: encountered improperly formatted JVM option in [%s] on line number [%d]: [%s]%s

What it means

Thrown by JvmOptionsParser when one or more lines in a jvm.options file are malformed (caught as JvmOptionsFileParserException and rewrapped as UserException CONFIG). The message lists each invalid line with its file and line number.

Source

Thrown at distribution/tools/server-cli/src/main/java/org/elasticsearch/server/cli/JvmOptionsParser.java:128

                e.jvmOptionsFile(),
                System.lineSeparator()
            );
            StringBuilder msg = new StringBuilder(errorMessage);
            int count = 0;
            for (final Map.Entry<Integer, String> entry : e.invalidLines().entrySet()) {
                count++;
                final String message = String.format(
                    Locale.ROOT,
                    "[%d]: encountered improperly formatted JVM option in [%s] on line number [%d]: [%s]%s",
                    count,
                    e.jvmOptionsFile(),
                    entry.getKey(),
                    entry.getValue(),
                    System.lineSeparator()
                );
                msg.append(message);
            }
            throw new UserException(ExitCodes.CONFIG, msg.toString());
        }
    }

    private List<String> jvmOptions(
        ServerArgs args,
        final Path config,
        Path tmpDir,
        final String esJavaOpts,
        final Map<String, String> substitutions,
        final Map<String, String> cliSysprops,
        final MachineDependentHeap machineDependentHeap
    ) throws InterruptedException, IOException, JvmOptionsFileParserException, UserException {

        final List<String> jvmOptions = readJvmOptionsFiles(config);

        if (esJavaOpts != null) {
            jvmOptions.addAll(Arrays.stream(esJavaOpts.split("\\s+")).filter(Predicate.not(String::isBlank)).toList());
        }

View on GitHub (pinned to db6a809a66)

Solutions

Use the line number from the message to open jvm.options and inspect the exact offending line.
Ensure every non-comment, non-blank line is a single valid JVM flag (-D, -X, or -XX:...).
For values with spaces, use the appropriate JVM syntax (usually no spaces; use = for -D props).
Re-run after editing to confirm zero parse errors.

Example fix

# jvm.options — before (line 42 malformed)
-Xmx4g extra

# after
-Xmx4g

Defensive patterns

Strategy: validation

Validate before calling

for (String line : Files.readAllLines(jvmOptionsFile)) {
    String t = line.trim();
    if (t.isEmpty() || t.startsWith("#")) continue;
    if (!t.startsWith("-D") && !t.startsWith("-X") && !t.startsWith("-XX:")) {
        throw new IllegalArgumentException("Invalid JVM option line: " + line);
    }
}

Try / catch

try {
    parser.jvmOptions(args, config, tmpDir, envOptions, substitutions, cliSysprops, mdh);
} catch (JvmOptionsFileParserException e) {
    throw new UserException(ExitCodes.CONFIG, "Fix jvm.options: " + e.invalidLines());
}

Prevention

Lint jvm.options changes: each non-blank, non-comment line must be a single JVM flag.
Avoid spaces inside option values; use = for -D properties.
Validate config in CI before deploying.

When it happens

Trigger: A line in config/jvm.options or a vendor jvm.options file does not conform to the expected JVM-option syntax — e.g. contains stray characters, is not a -D/-X/-XX flag, or has whitespace in the middle of an option.

Common situations: Manually editing jvm.options and introducing a typo; copy-pasting a multi-word value without quoting; a CI pipeline templating jvm.options that emits a blank/garbage line.

Related errors

AI-assisted analysis of elastic/elasticsearch@db6a809a66 (2026-08-12). Data as JSON: /api/errors/a3eff1bdcf56d683. Report an issue: GitHub.