Re: Restarting Nutch

[Sami Siren]

[moving this to nutch-user]

Hrishikesh Agashe wrote:

Hi,

 


I am planning to do a huge crawl using Nutch (billions of URLs) and so need
to understand whether Nutch can handle restarts after a crash.

 


For single system, if I do Ctrl+C while Nutch is running and then restart
it, will it be possible for Nutch to detect where it has reached in last run
and start from that point onwards? Or will it be considered as new fresh
crawl?
  

Nutch does not try to resume the action that was interrupted.

Also if I have 5 nodes running Nutch and doing the crawling, if one of the
node fails, should it be considered as total failure of Nutch itself? Or
should I allow other nodes to proceed further? Will I loose data gathered by
the failed node?
  
Hadoop will execute the remaining tasks at nodes that are available. 
Usually data will be stored on a shared/distributed filesystem (like 
HDFS). If your setup is similar and you ensure that the filesystem can 
survive single node failures your data should be safe.


--
Sami Siren

Restarting Nutch

[Hrishikesh Agashe]

Hi,

 

I am planning to do a huge crawl using Nutch (billions of URLs) and so need
to understand whether Nutch can handle restarts after a crash.

 

For single system, if I do Ctrl+C while Nutch is running and then restart
it, will it be possible for Nutch to detect where it has reached in last run
and start from that point onwards? Or will it be considered as new fresh
crawl?

 

Also if I have 5 nodes running Nutch and doing the crawling, if one of the
node fails, should it be considered as total failure of Nutch itself? Or
should I allow other nodes to proceed further? Will I loose data gathered by
the failed node?

 

TIA,

--Hrishi

 


DISCLAIMER
==
This e-mail may contain privileged and confidential information which is the 
property of Persistent Systems Ltd. It is intended only for the use of the 
individual or entity to which it is addressed. If you are not the intended 
recipient, you are not authorized to read, retain, copy, print, distribute or 
use this message. If you have received this communication in error, please 
notify the sender and delete all copies of this message. Persistent Systems 
Ltd. does not accept any liability for virus infected mails.