<http://www.uwasa.fi/~ts/http/expiry.html> Copyright © 1990-2005 by Prof. Timo Salmi Last modified Fri 30-Dec-2005 07:40:37

Counting since 5.11.2005

  

How long will my posting stay on the Usenet news?

There are some Usenet news related questions which cannot have a unique answer. This is one of them.

Each site (your host) receiving the newsfeed can define how long a news posting is kept before it is deleted, that is before it expires. The expiry can even be made to vary at a site depending on the newsgroup. In fact this is fairly common. The default expiry lengths at the various sites are influenced by many factors like local policy, the relevance of the newsgroup, the capacity of the local newsserver computer, and so on.

The current Usenet news volumes are staggering. This puts pressures on many sites to use quick expiry spans. Since the news travel at different speeds from the different parts of the net, and parts of the net may occasionally be down along the feed, the news arrive at differing lags. Unfortunately this means that at worst some newspostings can even have expired when they finally arrive.

If you look at the header of a news posting you will note an "Expires:" line in the header. This can be used to TRY to alter the expiry. The format is "Expires: Sun, 23 Apr 2000 10:00:00 GMT" without the double quotes. Please don't use this feature unless you have a very good reason and know what you are doing. Also note that many hosts override the users' expiry redefinitions.

If you wish to access older news postings that already have expired on your own server there is an extensive storage system at Google.

As always, be judicious about what you go and say on the Usenet news. Expiry is no guarantee against your postings being publicly available afterwards. (Even if you use the X-No-Archive: yes  header.)

The potential reasons include:

• The original posting has already expired at your site. See the first part of this FAQ item.
   
  
• The news propagate through the net unevenly. Thus it is not impossible that the answer posting has arrived at your location before the original question posting.
   
  
• The original posting has been canceled by the poster him/herself for one reason or another. It also is possible that the original posting was net abuse, such as spam, and has consequently been canceled by the poster's newsadmins or by a net abuse patrol.

• Disappearing Articles from the Resources for new Internet users.