Remote Logging

Overview

Alluxio supports sending logs to a remote log server over the network. This feature can be useful to system administrators who have to perform the task of log collection. With remote logging, the log files, e.g. master.log, worker.log, etc. on all Alluxio servers will be readily available on a designated and configurable directory on the log server.

Configure Alluxio

Refer to Running Alluxio on a cluster for instructions in deploying Alluxio in a cluster.

By default, remote logging is not enabled. To enable Alluxio remote logging, you can set three environment variables: ALLUXIO_LOGSERVER_HOSTNAME, ALLUXIO_LOGSERVER_PORT and ALLUXIO_LOGSERVER_LOGS_DIR.

There is no requirement on where the log server must run, as long as the other Alluxio servers have access to it. In our example, we run the log server on the same machine as a master.

Enable Remote Logging with Environment Variables

Suppose the hostname of the log server is AlluxioLogServer, and the port is 45010. In conf/alluxio-env.sh, add the following lines:

ALLUXIO_LOGSERVER_HOSTNAME=AlluxioLogServer
ALLUXIO_LOGSERVER_PORT=45010
ALLUXIO_LOGSERVER_LOGS_DIR=/tmp/alluxio_remote_logs

Restart Alluxio And Log Server

After making the modification to configuration, you need to restart the log server first. Then you can start Alluxio. This ensures that the logs that Alluxio generates during start-up phase will also go to the log server.

Start Log Server

On the log server, execute the following command.

$ ./bin/alluxio-start.sh logserver

Start Alluxio

On Alluxio master, execute the following command.

$ ./bin/alluxio-start.sh all

Verify Log Server Has Started

First, ssh to the machine on which log server is running.

Second, go to the directory where the log server has been configured to store logs received from other Alluxio servers. In the above example, the directory is /tmp/alluxio_remote_logs.

$ cd /tmp/alluxio_remote_logs
$ ls
master          proxy           secondary_master    worker
$ ls -l master/
...
-rw-r--r--  1 alluxio  alluxio  26109 Sep 13 08:49 34.204.198.64.log
...

You can see that the log files are put into different folders according to their type. Master logs are put in the folder master, worker logs are put in folder worker, etc. Within each folder, log files from different workers are distinguished by the IP/hostname of the machine on which the server has been running.

Need help? Ask a Question