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sks(8)			    SKS	OpenPGP	Key server			sks(8)

       SKS - Synchronizing Key Server

       sks [options] -debug

       SKS is a	OpenPGP	keyserver whose	goal is	to provide easy	to deploy,
       decentralized, and highly reliable synchronization. That	means that a
       key submitted to	one SKS	server will quickly be distributed to all key
       servers,	and even wildly	out-of-date servers, or	servers	that
       experience spotty connectivity, can fully synchronize with rest of the

       The design of SKS is deliberately simple. The server consists of	two
       single-threaded processes. The first, "sks db", fulfills	the normal
       jobs associated with a public key server, such as answering web
       requests. The only special functionality	of "sks	db" is that it keeps a
       log summarizing the changes to the key database.	"sks recon" does all
       the work	with respect to	reconciling hosts databases. "sks recon" keeps
       track of	specialized summary information	about the database, and	can
       use that	information to efficiently determine the differences between
       its database and	that of	another	host.

       Highly efficient	and reliable reconciliation algorithm

       Follows RFC2440 and RFC2440bis carefully	- unlike PKS, SKS supports new
       and old style packets, photoID packets, multiple	subkeys, and pretty
       much everything allowed by the RFCs.

       Fully compatible	with PKS system	- can both send	and receive syncs from
       PKS servers, ensuring seamless connectivity.

       Simple configuration:  each host	just needs a (partial) list of the
       other participating key servers.	Gossip is used to distribute
       information without putting a heavy load	an any one host.

       Supports	HKP/web-based querying,	and soon-to-be-standard	machine
       readable	indices

       SKS binary command options are as follows:

	    Initiates database server.

	   Initiates reconciliation server.

	   Apply filters to all	keys in	database, fixing some common problems.

	   Build key database, including body of keys directly in database.

       fastbuild -n [size] -cache [mbytes]
	   Build key database, doesn't include keys directly in	database,
	   faster than build. -n specifies the number of keydump files to read
	   per pass when used with build and the multiple of 15,000 keys to be
	   read	per pass when used with	fastbuild.  -cache specifies the
	   database cache to use in megabytes.

       pbuild -cache [mbytes] -ptree_cache [mbytes]
	   Build prefix-tree database, used by reconciliation server, from key
	   database. Allows for	specification of cache for key database	and
	   for ptree database.

       dump numkeys dumpdir <filename-prefix>
	   Create a raw	dump of	the keys in the	database. The dump is split
	   into	multiple files;	the numkeys parameter determines the number of
	   keys	dumped in each file. The optional filename-prefix is prepended
	   to the dump file names. Without it the dump files are named
	   0000.pgp, 0001.pgp,...

	   Adds	key from key files to existing database.

	   Drops key from database.

       update_subkeys [-n # of updates / 1000]
	   Updates subkey keyid	index to include all current keys. Only	useful
	   when	upgrading versions 1.0.4 or before of SKS.

	   prints SKS version and linked version of Berkeley DB	to stdout

	   Prints the help message.

       You won't need most of the options below	for normal operation. These
       options can be given in basedir/sksconf or as command line option for
       the sks binary.

	   Debugging mode.

	   Debugging level -- sets verbosity of	logging.

	    Number of bits defining a bin.

	   Number of errors that can be	corrected in one shot.

	   Seed	used by	RNG.

	   Current hostname.

	   Current nodename.

	    Number of keys to drop at random when synchronizing.

	    Number of keydump files to load at once.

	   Maximum number of matches for most specific word in a multi-word

	   Maximum number of matches that will be returned from	a query.

	   Maximum number of uid fetches performed in a	verbose	index query.

	   Pagesize in 512 byte	chucks for key db.

	   Pagesize in 512 byte	chucks for keyid db.

	   Pagesize in 512 byte	chucks for metadata db.

	   Pagesize in 512 byte	chucks for subkeyid db.

	   Pagesize in 512 byte	chucks for time	db.

	   Pagesize in 512 byte	chucks for tqueue db.

	   Pagesize in 512 byte	chunks for word	db.

	   Cache size in megs for key db.

	   Pagesize in 512 byte	chunks for prefix tree db.

	   Cache size in megs for prefix tree db.

	   Set base port number.

	   Set recon port number.

	   Set recon binding addresses.	 Can be	a list of whitespace separated
	   IP addresses	or domain names.

	   Set hkp port	number.

	   Set hkp binding addresses.  Can be a	list of	whitespace separated
	   IP addresses	or domain names.

	   Have	the HKP	interface listen on port 80, as	well as	the hkp_port.

	   Set base directory.

	   Send	log messages to	stdout instead of log file.

	   Use a disk-based ptree implementation. Slower, but requires far
	   less	memory.

	   Use in-mem ptree.

	   Maximum number of allowed ptree nodes. Only meaningful if
	   -diskptree is set.

	   Set probability. Used for testing code only.

	   Set sync interval for reconserver.

	   Set time between gossips in minutes.

	   Don't gossip	automatically. Host will still respond to requests
	   from	other hosts.

	   Set sync interval for dbserver.

	   Time	period between checkpoints.

	   Time	period between checkpoints for reconserver.

	   Multiple of thresh which specifies minimum node size	in prefix

	   Multiple of thresh which specifies minimum node size	that is
	   included in reconciliation.

	   Maximum number of differences to recover in one round.

	   Number of keys for reconserver to fetch from	dbserver in one	go.

	   Timeout in seconds for webserver requests.

	   Timeout for reconciliation runs in minutes.

	   Hour	at which to run	database statistics.

	   Runs	database statistics calculation	on boot.

	   Set timeout in seconds for initial exchange of config info in

	   Timeout in seconds for get_missing_keys.

	   Timeout in seconds for commands set over command socket.

	   Command used	for sending mail.

	   From	address	used in	synchronization	emails used to communicate
	   with	PKS.

	   When	doing a	database dump, only dump new keys, not keys already
	   contained in	a keydump file.

	   Maximum number of outstanding requests in reconciliation.

	   Maximum interval (in	hours) at which	membership file	is reloaded.

	   Disable sending of PKS mailsync messages.  ONLY FOR STANDALONE

	   Disable logging of recent hashset diffs.

	   Set OpenPGP KeyID of	the server contact

       --help, -help
	   Read	keyids from stdin (sksclient only)

	   Displays list of options.

       Information about important files located in your SKS basedir.

	   The main SKS	executable.

	   The executable responsible for parsing incoming mails from PKS key

	   Script to generate an initial database.

	   The mailsync	should contains	a list of email	addresses of PKS
	   keyservers. This file is important, because it ensures that keys
	   submitted directly to an SKS	keyserver are also forwarded to	PKS
	   keyservers. IMPORTANT : don't add someone to	your mailsync file
	   without getting their permission first!

	   With	SKS, two hosts can efficiently compare their databases then
	   repair whatever differences are found.  In order to set up
	   reconciliation, you first need to find other	SKS servers that will
	   agree to gossip with	you. The hostname and port of the server that
	   has agreed to do so should be added to this file.

	   The configuration file for your SKS server.

       membership	11370 #	Comments are allowed 11370   #	Another	host with default ports

	    membership_reload_interval:	1

	    * ^Subject:	incremental
	    | /path/of/sks_add_mail /path/to/sks/directory

	    pgp-public-keys:	  "|/path/of/sks_add_mail /path/to/sks/directory"

	The SKS	website	is located at

       The first draft was written by Thomas Sjogren

0.1				  2014-05-03				sks(8)


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