Access logs for a running Flink app in YARN cluster

[xiatao123]

Any good way to get access container logs from a running Flink app in YARN cluster in EMR?

You can view the logs through YARN UI. But cannot programmatically access it and send to other services.

The log aggregator only runs when the application finishes or a minimum 3600 secs copy. Any way we can get the logs more frequently?

[杨力]

Maybe you can get them from yarn with rest API.

Tao Xia <[hidden email]> 于 2018年4月13日周五 上午8:09写道：

Any good way to get access container logs from a running Flink app in YARN cluster in EMR?

You can view the logs through YARN UI. But cannot programmatically access it and send to other services.

The log aggregator only runs when the application finishes or a minimum 3600 secs copy. Any way we can get the logs more frequently?

[Gary Yao-2]

Hi,

I see two options:

1. You can login to the slave machines, which run the NodeManagers, and access
the container logs. The path of the container logs can be configured in
yarn-site.xml with the key yarn.nodemanager.log-dirs. In my tests with EMR, the
logs are stored at /var/log/hadoop-yarn/containers/ by default. For example:

  sudo ls /var/log/hadoop-yarn/containers/application_1523645835493_0002/container_1523645835493_0002_01_000002
  taskmanager.err  taskmanager.log  taskmanager.out

2. You can download the logs via HTTP from Flink:

  http://host:port/jobmanager/log
  http://host:port/taskmanagers/<taskmanager-id>/log

To get a list of taskmanagers:

  http://host:port/taskmanagers

Best,
Gary

On Fri, Apr 13, 2018 at 2:09 AM, Tao Xia <[hidden email]> wrote:

Any good way to get access container logs from a running Flink app in YARN cluster in EMR?

You can view the logs through YARN UI. But cannot programmatically access it and send to other services.

The log aggregator only runs when the application finishes or a minimum 3600 secs copy. Any way we can get the logs more frequently?

[xiatao123]

Thank you all for the tips. Will give a try.

On Fri, Apr 13, 2018 at 12:13 PM, Gary Yao <[hidden email]> wrote:

Hi,

I see two options:

1. You can login to the slave machines, which run the NodeManagers, and access
the container logs. The path of the container logs can be configured in
yarn-site.xml with the key yarn.nodemanager.log-dirs. In my tests with EMR, the
logs are stored at /var/log/hadoop-yarn/containers/ by default. For example:

  sudo ls /var/log/hadoop-yarn/containers/application_1523645835493_0002/container_1523645835493_0002_01_000002
  taskmanager.err  taskmanager.log  taskmanager.out

2. You can download the logs via HTTP from Flink:

  http://host:port/jobmanager/log
  http://host:port/taskmanagers/<taskmanager-id>/log

To get a list of taskmanagers:

  http://host:port/taskmanagers

Best,
Gary

On Fri, Apr 13, 2018 at 2:09 AM, Tao Xia <[hidden email]> wrote:

Any good way to get access container logs from a running Flink app in YARN cluster in EMR?

You can view the logs through YARN UI. But cannot programmatically access it and send to other services.

The log aggregator only runs when the application finishes or a minimum 3600 secs copy. Any way we can get the logs more frequently?