innd, inndstart - InterNetNews daemon
innd [ -a ] [ -c days ] [ -d ] [ -f ] [ -i count ] [ -o count ] [ -l size
] [ -m mode ] [ -n flag ] [ -p port ] [ -r ] [ -s ] [ -S host ] [ -t
timeout ] [ -u ] [ -x ] [ -L ] [ -N ] [ -H count ] [ -T count ] [ -X
inndstart [ flags ]
Innd, the InterNetNews daemon, handles all incoming NNTP feeds. It reads
the active(5) , newsfeeds(5) , and hosts.nntp(5) files into memory. It
then opens the NNTP port to receive articles from remote sites (see the
``-p'' option), When <config$HAVE_UNIX_DOMAIN> == DO, a Unix-domain
stream socket to receive articles from local processes such as nnrpd(8)
and rnews(1) , and a Unix-domain datagram socket for use by ctlinnd(8) .
When <config$HAVE_UNIX_DOMAIN> is not DO named pipes are used instead.
ctlinnd(8) is used to direct the server to perform certain actions. It
also opens the history(5) database and two log files to replace its
standard output and standard error.
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
set as <config$DEFAULT_TIMEOUT> (typically 300) seconds.
If innd gets an NOSPC error (see intro(2)) while trying to write the
active file, an article file, or the history database, it will send
itself a ``throttle'' command. This will also happen if it gets too many
I/O errors while writing to any files. If <config$INND_NICE_KIDS> == DO,
any sub-processes spawned by the server will get a nice(2) value of
<config$INND_NICE_VALUE> (typically 4.)
-p If the ``-p'' flag is used, then the NNTP port is assumed to be open
on the specified descriptor. (If this flag is used, then innd
assumes it is running with the proper permissions and it will not
call chown(2) on any files or directories it creates.)
-t Change the timeout period before flushing to timeoutseconds.
-i To limit the number of incoming NNTP connections, use the ``-i''
flag. A value of zero will suppress this check. The default is set
by <config$DEFAULT_CONNECTIONS> (typically 50.)
-o 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.
-l 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.
-c 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 set by <config$DEFAULT_CUTOFF>
Innd normally puts itself into the background, sets its standard
output and error to log files, and disassociates itself from the
terminal. Using the ``-d'' flag instructs the server to not do
this, while using the ``-f'' flag just leaves the server running the
-u The logs are normally buffered; use the ``-u'' flag to have them
-m To start the server in a paused or throttled state (see ctlinnd(8) )
use the ``-m'' flag to set the initial running mode. The argument
should start with a single letter g, p, or t, to emulate the ``go,''
``pause,'' or ``throttle'' commands, respectively.
-r If the ``-r'' flag is used, the server will renumber the active file
as if a ``renumber'' command were sent.
-s If the ``-s'' flag is used, then innd will not do any work but will
instead just check the syntax of the newsfeeds file. It will exit
with an error status if there are any errors; the actual errors will
be reported in syslog(3).
-n The ``-n'' flag specifies whether or not pausing or throttling the
server should also disable future newsreading processes. A value of
``y'' will make newreaders act as the server, a value of ``n'' will
allow newsreading even when the server is not running. The default
behavior is set by <config$ALLOW_READERS>.
-S 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''
-a 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.
-L If the ``-L'' flag is used, then innd will not create the links for
cross posted articles. A feed only type of site could use this
option to improve performance. Or it can be combined with a channel
feed to the crosspost(8) program to move the delay associated with
creating the links out of the innd processing loop.
-C If the ``-C'' flag is used, then innd will accept and propagate but
not actually process cancel or supercedes messages. This is
intended for sites concerned about abuse of cancels and wish to use
another cancel mechanism with greater authentication.
-H -T -X
The ``-H'', ``-T'', and ``-X'' flags control the number of connects
per minute allowed. This code is meant to protect your server from
newsreader clients that make too many connects per minute to your
server. You should probably not use it unless you are having a
problem. The table used for these checks is fixed at 128 entries
and is used as a ring. The size was chosen to make calculating the
index easy and to be pretty sure you won't run out of space. In
practice, it is doubtful that you will use even half the table at
any given moment.
The ``-H'' flag limits the number of times a host is allowed to
connect to the server per ``-X'' seconds. The default is 2.
The ``-T'' flag limits the total number of incoming connects to innd
per ``-X'' seconds. The maximum value is 128. The default is 60.
The ``-X'' sets the number of seconds used by the ``-H'' and ``-T''
flags. A value of zero turns off checking. The default is 0.
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.
Arriving articles that have a Control header or have a Subject header
that starts with the five characters ``cmsg\ '' are called control
messages. Except for the cancel message, these messages are implemented
by external programs in the <config$_PATH_CONTROLPROGS> directory
(typically /usr/news/bin/control.) (Cancel messages update the history
database, so they must be handled internally; the cost of syncing,
locking, then unlocking would be too high given the number of cancel
messages that are received.)
When a control message arrives, the first word of the text is converted
to lowercase and used as the name of the program to execute; if the named
program does not exist, then a program named
<config$_PATH_BADCONTROLPROG> (typically 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
The distribution of control message is also different from those of
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.
When <config$MERGE_TO_GROUPS> == DO, if an article is posted to a
newsgroup that starts with the three letters ``to.'' it will get special
treatment if the newsgroup does not exist in the active file: the
article is filed into the newsgroup ``to'' and it is sent to the first
site named after the prefix. For example, a posting to ``to.uunet'' will
be filed in ``to'' and sent to the site ``uunet.''
Innd implements the NNTP commands defined in RFC 977, with the following
1. The ``list'' maybe followed by an optional ``active'',
``active.times'', or ``newsgroups'' argument. This common extension
is not fully supported; see nnrpd(8) .
2. The ``authinfo user'' and ``authinfo pass'' commands are
implemented. These are based on the reference Unix implementation;
no other documentation is available.
3. A new command, ``mode reader'', is provided. This command will
cause the server to pass the connection on to nnrpd. The command
``mode query'' is intended for future use, and is currently treated
the same way.
4. A new command, ``xreplic news.group/art[,news.group/art]'', is
provided. This is similar to the ``ihave'' command (the same reply
codes are used) except for the data that follows the command word.
The data consists of entries separated by a single comma. Each
entry consists of a newsgroup name, a slash, and an article number.
Once processed, the article will be filed in the newsgroup and
article numbers specified in the command.
5. A new command, ``xpath messageid'', is provided. The server
responds with a 223 response and a space-separated list of filenames
where the article was filed.
6. The only other commands implemented are ``head'', ``help'',
``ihave'', ``quit'', and ``stat''.
Innd modifies as few article headers as possible, although it could be
better in this area.
The following headers, if present, are removed:
Empty headers and headers that consist of nothing but whitespace are also
The local site's name (as determined by the ``pathhost'' value in
inn.conf(5)) and an exclamation point are prepended to the Path header.
The Xref header is removed. If the article is cross-posted a new header
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.
Innd reports all incoming articles in its log file. This is a text file
with a variable number of space-separated fields in one of the following
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 first three fields are the date and time to millisecond resolution.
The fifth field is the site that sent the article (based on the Path
header) and the sixth field is the article's Message-ID; they will be a
question mark if the information is not available.
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 "%s" header
EOF in headers
Linecount %s != %s +- %s
Missing %s header
No colon-space in "%s" header
Space before colon in "%s" header
Too old -- "%s"
Unapproved for "%s"
Unwanted newsgroup "%s"
Unwanted distribution "%s"
Whitespace in "Newsgroups" header -- "%s"
Where ``%s'', above, is replaced by more specific information.
Note that when <config$WANT_TRASH> == DO, if an article is accepted and
none of the newsgroups are valid, it will be logged with two lines, a
``j'' line and a minus sign line.
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.
Written by Rich $alz <email@example.com> for InterNetNews. This is
revision 1.37, dated 1996/12/06.
active(5) , ctlinnd(8) , crosspost(8) , dbz(3z), history(5) , hosts.nntp(5) ,
inn.conf(5) , newsfeeds(5) , nnrpd(8) , rnews(1) , syslog(8).
You can find a summary and links related to this topic
as part of the Mib Software Usenet RKT.