Once the files and sockets have been opened, innd waits for connections and data to be ready on its ports by using select(2) and non-blocking I/O. If no data is available, then it will flush its in-core data structures. The default number of seconds to timeout before flushing is 300 seconds. This timeout may be changed by using the ``-t'' flag.
To limit the number of incoming NNTP connections, use the ``-i'' flag. A value of zero will suppress this check. The default is 50.
To limit the number of files that will be kept open for outgoing file feeds, use the ``-o'' flag. The default is the number of available descriptors minus some reserved for internal use.
To limit the size of an article, use the ``-l'' flag. If this flag is used, then any article bigger than size bytes will be rejected. The default is no checking, which can also be obtained by using a value of zero.
Innd rejects articles that are too old. While this behavior can be controlled by the history database, occasionally a site dumps a batch of very old news back onto the network. Use the ``-c'' flag to specify a cutoff. For example ``-c21'' will reject any articles that were posted more than 21 days ago. A value of zero will suppress this check. The default is 14 days.
Innd normally puts itself into the background, sets its standard output and error to log files, and disassociates itself from the terminal. Using the ``-d'' flag instructs the server to not do this, while using the ``-f'' flag just leaves the server running the foreground. The logs are normally buffered; use the ``-u'' flag to have them unbuffered.
To start the server in a paused or throttled state (see ctlinnd(8)) use the ``-m'' flag to set the initial running mode. The argument should start with a single letter g, p, or t, to emulate the ``go,'' ``pause,'' or ``throttle'' commands, respectively.
If the ``-r'' flag is used, the server will renumber the active file as if a ``renumber'' command were sent.
If the ``-s'' flag is used, then innd will not do any work but will instead just check the syntax of the newsfeeds file. It will exit with an error status if there are any errors; the actual errors will be reported in syslog(3).
If innd gets an NOSPC error (see intro(2)) while trying to write the active file, an article file, or the history database, it will send itself a ``throttle'' command. This will also happen if it gets too many I/O errors while writing to any files. value of 10.
The ``-n'' flag specifies whether or not pausing or throttling the server should also disable future newsreading processes. A value of ``y'' will make newreaders act as the server, a value of ``n'' will allow newsreading even when the server is not running. The default is to allow reading.
If the ``-S'' flag is used, then innd will run in ``slave'' mode. When running as a slave, the server will only accept articles from the specified host, which must use the ``xreplic'' protocol extension described below. Note that the host must either appear in the hosts.nntp file, or the server must be started with the ``-a'' flag.
By default, if a host if not mentioned in the hosts.nntp file, then the connection is handed off to nnrpd. If the ``-a'' flag is used, then any host can connect and transfer articles.
If the ``-x'' flag is used, then an Xref header will be added to all articles even if they are not cross-posted.
Inndstart is a small front-end program that opens the NNTP port, sets its userid and groupid to the news maintainer, and then execs innd with the ``-p'' flag and a minimal secure, environment. This is a small, easily-understood front-end program that can be used if a site does not want to run innd with root privileges.
When a control message arrives, the first word of the text is converted to lowercase and used as the name of the program to execute; if the named program does not exist, then a program named default is executed.
All control programs are invoked with four parameters. The first is the address of the person who posted the message; this is taken from the Sender header. If that header is empty, then it is taken from the From header. The second parameter is the address to send replies to; this is taken from the Reply-To header. If that header is empty then the poster's address is used. The third parameter will be a name under which the article is filed, relative to the news spool directory. The fourth parameter is the host that sent the article, as specified on the Path line.
The distribution of control message is also different from those of standard articles.
Control messages are normally filed in the newsgroup named control. They can be filed in subgroups, however, based on the control message command. For example, a newgroup message will be filed in control.newgroup if that group exists, otherwise it will be filed in control.
Sites may explicitly have the ``control'' newsgroup in their subscription list, although it is usually best to exclude it. If a control message is posted to a group whose name ends with the four characters ``.ctl'' then the suffix is stripped off and what is left is used as the group name. For example, a cancel message posted to ``news.admin.ctl'' will be sent to all sites that subscribe to ``control'' or ``news.admin.'' Newgroup and rmgroup messages receive additional special treatment. If the message is approved and posted to the name of the group being created or removed, then the message will be sent to all sites whose subscription patterns would cause them to receive articles posted in that group.
The following headers, if present, are removed:
Date-Received Posted Posting-Version Received Relay-Version
The local site's name and an exclamation point are prepended to the Path header.
The Xref header is removed. If the article is cross-posted a new header is generated.
The Lines header will be added if it is missing.
Innd does not rewrite incorrect headers. For example, it will not replace an incorrect Lines header, but will reject the article.
mon dd hh:mm:ss.mmm + feed <Message-ID> site... mon dd hh:mm:ss.mmm j feed <Message-ID> site... mon dd hh:mm:ss.mmm c feed <Message-ID> site... mon dd hh:mm:ss.mmm - feed <Message-ID> reason...
The fourth field indicates whether the article was accepted or not. If it is a plus sign, then the article was accepted. If it is the letter ``j'' then the article was accepted, but all of newsgroups have an ``j'' in their active field, so the article was filed into the ``junk'' newsgroup. If the fourth field is the letter ``c'', then a cancel message was accepted before the original article arrived. In all three cases, the article has been accepted and the ``site..'' field contains the space-separated list of sites to which the article is being sent.
If the fourth field is a minus sign, then the article was rejected. The reasons for rejection include:
"%s" header too long "%s" wants to cancel <%s> by "%s" Article exceeds local limit of %s bytes Article posted in the future -- "%s" Bad "%s" header Can't write history Duplicate Duplicate "%s" header EOF in headers Linecount %s != %s +- %s Missing %s header No body No colon-space in "%s" header No space Space before colon in "%s" header Too old -- "%s" Unapproved for "%s" Unwanted newsgroup "%s" Unwanted distribution "%s" Whitespace in "Newsgroups" header -- "%s"
Innd also makes extensive reports through syslog. The first word of the log message will be the name of the site if the entry is site-specific (such as a ``connected'' message). The first word will be ``ME'' if the message relates to the server itself, such as when a read error occurs.
If the second word is the four letters ``cant'' then an error is being reported. In this case, the next two words generally name the system call or library routine that failed, and the object upon which the action was being performed. The rest of the line may contain other information.
In other cases, the second word attempts to summarize what change has been made, while the rest of the line gives more specific information. The word ``internal'' generally indicates an internal logic error.