Christophe Wolfhugel <Christophe.Wolfhugel@grasp.insa-lyon.fr> writes:

Having some of your NNTP newsfeeds delayed by a fixed amount of time is
a good way to reduce your bandwidth requirements, or a good way to set
up a backup-feed.  By including a Wt flag in your newsfeeds file, INN
will insert timestamp entries in that batchfile, channels, or
exploders.  This timestamp can be used to implement delayed
ihave/sendme processing.  INN's senders (like innxmit) do not use that
data yet.  However, NNTPLINK does support this delayed IHAVE/SENDME
mechanism since release 3.3  (NNTPLINK can be found on
shape.mps.ohio-state.edu:/pub/nntplink/nntplink.tar.gz).

HOW TO DO IT:

The syntax that you would use in your newsfeeds file would be:

	site:*:Tf,Wtmn:

and run this command now and then:

	nntplink -i batchfile -y 300 -b site news.site.fr

The delayed IHAVE/SENDME is expected to allow bandwidth savings in
situations where all sites use nntplink in following topology:

	Your site -- 64k -----------+-----------  Site 1
	                            |               |
	                            |              2mb
	                            |               |
	                            +------------ Site 2

   Site 1 and 2 are in the same metropolitan area, you feed them both.
   With the standard nntplink layout, you generally send all articles
   twice, which is a waste even if you're at 2 Meg/s link and even if
   Site 1 and 2 do nntplinks, you're faster.

   The delayed link would be used between your site and Site 2.  A 2 or
   3 minute delay allows Site 1 to feed Site 2 before you, and in case
   of a Site 1 outage the backup starts nearly immediately.

   Reasonable delays are still kept as You -> 1 -> 2 should take less
   than one minute (or just 300 ms disk to disk if using nntplink -i ? :)).

Experiences seem to show that a 2 to 3 minutes delay is
a reasonable choice.

Chris

© 2008 FAQS.ORG. All rights reserved.