.TH EXPORTFS 4 .SH NAME exportfs, srvfs \- network file server plumbing .SH SYNOPSIS .B exportfs [ .B -adnsR ] [ .B -f .I dbgfile ] [ .B -m .I msize ] [ .B -r .I root ] [ .B -S .I service ] [ .B -A announce ] [ .B -e .I "'enc auth'" ] [ .B -N .I nsfile ] [ .B -P .I patternfile ] .PP .B srvfs [ .B -dR ] [ .B -p .I perm ] [ .B -P .I patternfile ] [ .B -e .I exportprog ] .I name .I path .SH DESCRIPTION .I Exportfs is a user level file server that allows Plan 9 compute servers, rather than file servers, to export portions of a name space across networks. The service is started either by the .IR cpu (1) command or by a network listener process. An initial protocol establishes a root directory for the exported name space. The connection to .I exportfs is then mounted, typically on .BR /mnt/term . .I Exportfs then acts as a relay file server: operations in the imported file tree are executed on the remote server and the results returned. This gives the appearance of exporting a name space from a remote machine into a local file tree. .PP .I Exportfs creates a new name space for each connection, using .B /lib/namespace by default (see .IR namespace (6)). The .B -n option gives an alternative name space file. .PP The .B -R option makes the served name space read only. .PP The .B -r option bypasses the initial protocol, instead immediately serving the name space rooted at .IR root . The .B -s option is equivalent to .B -r .BR / , but predates .B -r and remains for compatibility. .PP The .B -S option also bypasses the initial protocol but serves the result of mounting .IR service . A separate mount is used for each .IR attach (5) message, to correctly handle servers in which each mount corresponds to a different client .IR e.g. , ( .IR rio (4)). .PP The .B -m option sets the maximum message size that exportfs should offer to send (see .IR version (5)); this helps tunneled 9P connections to avoid unnecessary fragmentation. .PP The .B -a option instructs .I exportfs to authenticate the user, usually because it is being invoked from a remote machine. .PP The .B -d option instructs .I exportfs to log all 9P traffic to .I dbgfile (default .BR /tmp/exportdb ). .PP The .BI -P patternfile option restricts the set of exported files. .I Patternfile contains one regular expression per line, to be matched against path names relative to the current working directory and starting with .BR ./ . For a file to be exported, all lines with a prefix .B + must match and all those with prefix .B - must not match. .PP The .B -e option specifies the encryption and authentication algorithms to use for encrypting the wire traffic. The defaults are .B rc4_256 and .BR sha1 . The full list of supported protocols in in .IR ssl (3). .PP The .B cpu command uses .I exportfs to serve device files in the terminal. The .IR import (4) command calls .I exportfs on a remote machine, permitting users to access arbitrary pieces of name space on other systems. Because the kernel disallows reads and writes on mounted pipes (as might be found in .BR /srv ), .I exportfs calls itself (with appropriate .B -m and .B -S options) to simulate reads and writes on such files. .PP .I Srvfs invokes .I exportprog (default .BR /bin/exportfs ) to create a mountable file system from a name space and posts it at .BI /srv/ name , which is created with mode .I perm (default 0600). By default, the name space is the directory tree rooted at .IR path . If the .BR -d , .BR -R , or .B -P options are given, .I srvfs passes them to .IR exportprog . .PP The .B -A filter specifies an announce string when exportfs is used in combination with aan. The announce string identifies the network and network protocol to use for aan connections. .SH EXAMPLES To export the archive of one user for one month, except for secrets, .IP .EX cd /n/dump echo '+ ^\.(/2003(/10..(/usr(/glenda/?)?)?)?)?' > /tmp/pattern echo '- \.(aes|pgp)$' >> /tmp/pattern exportfs -p /tmp/pattern .EE .LP Use .I srvfs to enable mounting of an FTP file system (see .IR ftpfs (4)) in several windows, or to publish a .B /proc (see .IR proc (3)) with a broken process so a remote person may debug the program: .IP .EX srvfs ftp /n/ftp srvfs broke /mnt/term/proc .EE .LP Use .I srvfs to obtain a copy of a service to be manipulated directly by a user program like .IR nfsserver (8): .IP .EX srvfs nfs.boot /srv/boot aux/nfsserver -f /srv/nfs.boot .EE .SH SOURCE .B /sys/src/cmd/exportfs .br .B /sys/src/cmd/srvfs.c .SH SEE ALSO .IR aan (8), .IR import (4), .IR exportfs (4)