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INN FAQ Part 6

NOTE: The maintainers of the INN FAQ stopped publishing in December 1997.
An important update to this topic is provided by Mib Software in the Usenet RKT for Subscribers.

Subject: (6.12) How do I set up a delayed IHAVE/SENDME over NNTP?

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


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


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.



[Source: INN FAQ Part 6 Archive-name: usenet/software/inn-faq/part6]
[Last Changed: $Date: 1997/07/01 01:25:41 $ $Revision: 2.21 $]
[Copyright: 1997 Heiko Rupp, portions by Tom Limoncelli, Rich Salz, et al.]