You must set the VECSUM_PASSES environment variable to the n

Error message

You must set the VECSUM_PASSES environment variable to the number of passes to make.

What it means

Error "You must set the VECSUM_PASSES environment variable to the number of passes to make. " thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfs-tests/vecsum.c:198

    length_str = getenv("VECSUM_LENGTH");
    if (!length_str) {
        length_str = "2147483648";
    }
    opts->length = atoll(length_str);
    if (!opts->length) {
        fprintf(stderr, "Can't parse VECSUM_LENGTH of '%s'.\n",
                length_str);
        goto error;
    }
    if (opts->length % VECSUM_CHUNK_SIZE) {
        fprintf(stderr, "VECSUM_LENGTH must be a multiple of '%lld'.  The "
                "currently specified length of '%lld' is not.\n",
                (long long)VECSUM_CHUNK_SIZE, (long long)opts->length);
        goto error;
    }
    pass_str = getenv("VECSUM_PASSES");
    if (!pass_str) {
        fprintf(stderr, "You must set the VECSUM_PASSES environment "
            "variable to the number of passes to make.\n");
        goto error;
    }
    opts->passes = atoi(pass_str);
    if (opts->passes <= 0) {
        fprintf(stderr, "Invalid value for the VECSUM_PASSES "
            "environment variable.  You must set this to a "
            "number greater than 0.\n");
        goto error;
    }
    ty_str = getenv("VECSUM_TYPE");
    if (!ty_str) {
        fprintf(stderr, "You must set the VECSUM_TYPE environment "
            "variable to " VECSUM_TYPE_VALID_VALUES "\n");
        goto error;
    }
    ty = parse_vecsum_type(ty_str);
    if (ty < 0) {

View on GitHub (pinned to 2add963021)

Solutions

Export VECSUM_PASSES with a positive integer, e.g. export VECSUM_PASSES=3.

When it happens

Trigger: vecsum startup validation: the VECSUM_PASSES environment variable is unset.

Common situations: User launched vecsum without specifying how many read passes to perform.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/b47ee0b9fc3b1c46. Report an issue: GitHub.