apache/hadoop · error

hdfsConnCheckKpath(conn.usrname=%s): mtime on '%s' has chang

Error message

hdfsConnCheckKpath(conn.usrname=%s): mtime on '%s' has changed from '%s' to '%s'.  Condemning the connection because our cached Kerberos credentials have probably changed.

What it means

Error "hdfsConnCheckKpath(conn.usrname=%s): mtime on '%s' has changed from '%s' to '%s'. Condemning the connection because our cached Kerberos credentials have probably changed. " thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/fuse-dfs/fuse_connect.c:308

  if (stat(conn->kpath, &st) < 0) {
    ret = errno;
    if (ret == ENOENT) {
      fprintf(stderr, "hdfsConnCheckKpath(conn.usrname=%s): the kerberos "
              "ticket cache file '%s' has disappeared.  Condemning the "
              "connection.\n", conn->usrname, conn->kpath);
    } else {
      fprintf(stderr, "hdfsConnCheckKpath(conn.usrname=%s): stat(%s) "
              "failed with error code %d.  Pessimistically condemning the "
              "connection.\n", conn->usrname, conn->kpath, ret);
    }
    return -ret;
  }
  if ((st.st_mtim.tv_sec != conn->kPathMtime) ||
      (st.st_mtim.tv_nsec != conn->kPathMtimeNs)) {
    timeToStr(conn->kPathMtime, prevTimeBuf, sizeof(prevTimeBuf));
    timeToStr(st.st_mtim.tv_sec, newTimeBuf, sizeof(newTimeBuf));
    fprintf(stderr, "hdfsConnCheckKpath(conn.usrname=%s): mtime on '%s' "
            "has changed from '%s' to '%s'.  Condemning the connection "
            "because our cached Kerberos credentials have probably "
            "changed.\n", conn->usrname, conn->kpath, prevTimeBuf, newTimeBuf);
    return -EINTERNAL;
  }
  return 0;
}

/**
 * Cache expiration logic.
 *
 * This function is called periodically by the cache expiration thread.  For
 * each FUSE connection not currently in use (refcnt == 0) it will decrement the
 * expirationCount for that connection.  Once the expirationCount reaches 0 for
 * a connection, it can be garbage collected.
 *
 * We also check to see if the Kerberos credentials have changed.  If so, the
 * connecton is immediately condemned, even if it is currently in use.

View on GitHub (pinned to 2add963021)

Solutions

1. Avoid refreshing or replacing the Kerberos ticket cache while fuse-dfs is running; re-run kinit and restart/retry the FUSE operation so a new connection with current credentials is established.

When it happens

Trigger: Thrown at hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/fuse-dfs/fuse_connect.c:308 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/5f3af1c5d7a4c255. Report an issue: GitHub.