innd(8)
NAME
innd, inndstart - InterNetNews daemon
SYNOPSIS
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 seconds ] inndstart [ flags ]
DESCRIPTION
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), 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) 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 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. Any sub-processes spawned by the server will get a nice(2) value of 10.
OPTIONS
-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
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 14 days.
-d -f 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.
-u The logs are normally buffered; use the ``-u'' flag to have them
unbuffered.
-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 is to allow reading.
-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'' flag.
-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.
CONTROL MESSAGES
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 /usr/lib/news/control directory. (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 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.
PROTOCOL DIFFERENCES
Innd implements the NNTP commands defined in RFC 977, with the
following differences:
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''.
HEADER MODIFICATIONS
Innd modifies as few article headers as possible, although it could be
better in this area.
The following headers, if present, are removed:
Date-Received
Posted
Posting-Version
Received
Relay-Version
Empty headers and headers that consist of nothing but whitespace are
also dropped.
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 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.
LOGGING
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 formats:
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
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"
Where ``%s'', above, is replaced by more specific information.
Note that 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.
HISTORY
Written by Rich $alz <[email protected]> for InterNetNews. This is revision 1.37, dated 1996/12/06.
SEE ALSO
active(5), ctlinnd(8), crosspost(8), dbz(3z), history(5), hosts.nntp(5), inn.conf(5), newsfeeds(5), nnrpd(8), rnews(1), syslog(8). INND(8)
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