Chris Neal 2012-08-13, 17:43
Stern, Mark 2012-08-13, 20:03
Patrick Wendell 2012-08-13, 23:28
-Re: Avro client in NG as replacement for tail source in OG?
Chris Neal 2012-08-14, 14:19
Thanks Mark and Patrick,
I had seen the ExecSource, and it's associated caveats :) That has two
problems for me:
1) It's aforementioned unreliability should the channel have errors, and
2) All my applications run on Solaris, whose tail command does not have a
-F equivalent from the Linux world. :(
I noticed that the wiki
mention a feature for NG for supporting a tail source, but no JIRA is
assigned to it yet. If that page is still up to date, I'm glad to see that
it's at least on the roadmap!
If anyone can think of any other creative ways to do this, please share.
On Mon, Aug 13, 2012 at 6:28 PM, Patrick Wendell <[EMAIL PROTECTED]> wrote:
> Hey Chris,
> Mark has got it - for the behavior you are looking, you probably want
> a tier of flume agents running where you currently have avro clients,
> using an exec source with "tail -F" as the command.
> Keep in minding the red warning box in the user guide related to
> sources like this. If a flume agent restarts, it may re-send or miss
> certain log entries.
> - Patrick
> On Mon, Aug 13, 2012 at 1:03 PM, Stern, Mark <[EMAIL PROTECTED]> wrote:
> > Use an exec source running 'tail -F'.
> > ________________________________________
> > From: Chris Neal [[EMAIL PROTECTED]]
> > Sent: Monday, August 13, 2012 8:43 PM
> > To: [EMAIL PROTECTED]
> > Subject: Avro client in NG as replacement for tail source in OG?
> > Hi all.
> > I have a very typical configuration:
> > Application logs to log4J file.
> > FlumeNG avro-client watches the file and sends events into FlumeNG Agent
> Tier 1
> > FlumeNG Agent Tier 1: AvroSource to FileChannel to AvroSink
> > FlumeNG Agent Tier 2: AvroSource to FileChannel to HDFSSink
> > I was noticing that after some time, the Tier 1 Agent would disconnect
> from the avro-client. What is happening is that the avro-client sends
> events to the Tier 1 Agent as fast as it can, and when it reaches the end
> of the file, it exits. The problem is, the application is still logging to
> the log4J file, but now all future events are lost because the avro-client
> has exited.
> > I thought the "-F" option to avro-client was like the "-F" option to
> tail, but after looking at the code, it is not. There seems to be no
> "follow" mode for the avro client that I can see. I then stumbled across
> this key sentence from here<
> > Think of the avro-client command as cat for Flume
> > So, it's a "cat", not a "tail".
> > So I'm wondering, what's the right/best/current way to emulate OG's
> > Much appreciated.
> > Chris
Chris Neal 2012-08-14, 15:00
Chris Neal 2012-08-14, 15:36
Patrick Wendell 2012-08-14, 20:15
Chris Neal 2012-08-15, 14:12