curator-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Miller, Austin" <Austin.Mil...@morganstanley.com>
Subject RE: Creating PersistentEphemeralNode when noauth leads to cycle
Date Thu, 23 Jul 2015 16:54:27 GMT
Hi Cameron,

Looking over the comments, the proposed change, to exit the loop by return, seems like a net
negative.  While it prevents hammering the server, it seems to do so by violating the PEN
contract, which I understood to be “If creating the node can eventually succeed, it will
succeed.”  Now with the caveat that retry for auth issues is up to the user.

The notion of using a watch on the parent node to wait for noauth to not be an issue seems
to be much superior, because it would allow the contract to remain, eventually the PEN will
succeed if it can succeed, while also not hammering the server.   I recognize the complexity
would increase as the need for doing things in the right order to prevent race conditions
would have to be properly thought through.

What happens if the parent node doesn’t exist?

Ultimately, could we tie failure back into the config retry somehow?  So that you can get
exponential backoff retry behavior in PEN?

Austin

From: Cameron McKenzie [mailto:mckenzie.cam@gmail.com]
Sent: Wednesday, July 22, 2015 7:40 PM
To: dev@curator.apache.org
Cc: Gupta, Abhishek (ICT); Miller, Austin (ICT)
Subject: Re: Creating PersistentEphemeralNode when noauth leads to cycle

This is definitely an issue, seems like it's the same problem as CURATOR-228. I can reproduce
it, will look at a fix when I get a minute.

On Wed, Jul 22, 2015 at 7:48 PM, Szekeres, Zoltan <Zoltan.Szekeres@morganstanley.com<mailto:Zoltan.Szekeres@morganstanley.com>>
wrote:
Hi Curator Dev!

We've encountered an issue when creating a PersistentEphemeralNode and the authentication
fails for the given path. We received a NOAUTH result code, which the BackgroundCallback's
processResult doesn't handle and tries to create the node again. This leads to a cycle. This
is an issue for us, because it can generate thousands of requests per minute.

We use curator 2.4.2 and zookeeper 3.4.6.

A possibly related JIRA:
https://issues.apache.org/jira/i#browse/CURATOR-228?jql=text%20~%20%22PersistentEphemeralNode%22

Do you see this as an issue?

Best Regards,
Zoltan Szekeres
Morgan Stanley | Institutional & Corporate Tech
Lechner Odon fasor 8 | Floor 05
Budapest, 1095
Phone: +36 1 881-4657<tel:%2B36%201%20881-4657>
Zoltan.Szekeres@morganstanley.com<mailto:Zoltan.Szekeres@morganstanley.com><mailto:Zoltan.Szekeres@morganstanley.com<mailto:Zoltan.Szekeres@morganstanley.com>>



________________________________

NOTICE: Morgan Stanley is not acting as a municipal advisor and the opinions or views contained
herein are not intended to be, and do not constitute, advice within the meaning of Section
975 of the Dodd-Frank Wall Street Reform and Consumer Protection Act. If you have received
this communication in error, please destroy all electronic and paper copies; do not disclose,
use or act upon the information; and notify the sender immediately. Mistransmission is not
intended to waive confidentiality or privilege. Morgan Stanley reserves the right, to the
extent permitted under applicable law, to monitor electronic communications. This message
is subject to terms available at the following link: http://www.morganstanley.com/disclaimers
If you cannot access these links, please notify us by reply message and we will send the contents
to you. By messaging with Morgan Stanley you consent to the foregoing.



________________________________

NOTICE: Morgan Stanley is not acting as a municipal advisor and the opinions or views contained
herein are not intended to be, and do not constitute, advice within the meaning of Section
975 of the Dodd-Frank Wall Street Reform and Consumer Protection Act. If you have received
this communication in error, please destroy all electronic and paper copies; do not disclose,
use or act upon the information; and notify the sender immediately. Mistransmission is not
intended to waive confidentiality or privilege. Morgan Stanley reserves the right, to the
extent permitted under applicable law, to monitor electronic communications. This message
is subject to terms available at the following link: http://www.morganstanley.com/disclaimers
If you cannot access these links, please notify us by reply message and we will send the contents
to you. By messaging with Morgan Stanley you consent to the foregoing.
Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message