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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] 6 .TH SHARE_NFS 1M "May 6, 2009" 7 .SH NAME 8 share_nfs \- make local NFS file systems available for mounting by remote 9 systems 10 .SH SYNOPSIS 11 .LP 12 .nf 13 \fBshare\fR [\fB-d\fR \fIdescription\fR] [\fB-F\fR nfs] [\fB-o\fR \fIspecific_options\fR] \fIpathname\fR 14 .fi 15 16 .SH DESCRIPTION 17 .sp 18 .LP 19 The \fBshare\fR utility makes local file systems available for mounting by 20 remote systems. It starts the \fBnfsd\fR(1M) and \fBmountd\fR(1M) daemons if 21 they are not already running. 22 .sp 23 .LP 24 If no argument is specified, then \fBshare\fR displays all file systems 25 currently shared, including \fBNFS\fR file systems and file systems shared 26 through other distributed file system packages. 27 .SH OPTIONS 28 .sp 29 .LP 30 The following options are supported: 31 .sp 32 .ne 2 33 .na 34 \fB\fB-d\fR \fIdescription\fR\fR 35 .ad 36 .sp .6 37 .RS 4n 38 Provide a comment that describes the file system to be shared. 39 .RE 40 41 .sp 42 .ne 2 43 .na 44 \fB\fB\fR\fB-F\fR \fBnfs\fR\fR 45 .ad 46 .sp .6 47 .RS 4n 48 Share \fBNFS\fR file system type. 49 .RE 50 51 .sp 52 .ne 2 53 .na 54 \fB\fB-o\fR \fIspecific_options\fR\fR 55 .ad 56 .sp .6 57 .RS 4n 58 Specify \fIspecific_options\fR in a comma-separated list of keywords and 59 attribute-value-assertions for interpretation by the file-system-type-specific 60 command. If \fIspecific_options\fR is not specified, then by default sharing is 61 read-write to all clients. \fIspecific_options\fR can be any combination of the 62 following: 63 .sp 64 .ne 2 65 .na 66 \fB\fBaclok\fR\fR 67 .ad 68 .sp .6 69 .RS 4n 70 Allows the \fBNFS\fR server to do access control for \fBNFS\fR Version 2 71 clients (running SunOS 2.4 or earlier). When \fBaclok\fR is set on the server, 72 maximal access is given to all clients. For example, with \fBaclok\fR set, if 73 anyone has read permissions, then everyone does. If \fBaclok\fR is not set, 74 minimal access is given to all clients. 75 .RE 76 77 .sp 78 .ne 2 79 .na 80 \fB\fBanon=\fR\fIuid\fR\fR 81 .ad 82 .sp .6 83 .RS 4n 84 Set \fIuid\fR to be the effective user \fBID\fR of unknown users. By default, 85 unknown users are given the effective user \fBID\fR \fBUID_NOBODY\fR. If 86 \fIuid\fR is set to \fB\(mi1\fR, access is denied. 87 .RE 88 89 .sp 90 .ne 2 91 .na 92 \fB\fIcharset\fR=\fIaccess_list\fR\fR 93 .ad 94 .sp .6 95 .RS 4n 96 Where \fIcharset\fR is one of: \fBeuc-cn\fR, \fBeuc-jp\fR, \fBeuc-jpms\fR, 97 \fBeuc-kr\fR, \fBeuc-tw\fR, \fBiso8859-1\fR, \fBiso8859-2\fR, \fBiso8859-5\fR, 98 \fBiso8859-6\fR, \fBiso8859-7\fR, \fBiso8859-8\fR, \fBiso8859-9\fR, 99 \fBiso8859-13\fR, \fBiso8859-15\fR, \fBkoi8-r\fR. 100 .sp 101 Clients that match the \fIaccess_list\fR for one of these properties will be 102 assumed to be using that character set and file and path names will be 103 converted to UTF-8 for the server. 104 .RE 105 106 .sp 107 .ne 2 108 .na 109 \fB\fBindex=\fR\fBfile\fR\fR 110 .ad 111 .sp .6 112 .RS 4n 113 Load \fBfile\fR rather than a listing of the directory containing this file 114 when the directory is referenced by an \fBNFS URL\fR. 115 .RE 116 117 .sp 118 .ne 2 119 .na 120 \fB\fBlog=tag\fR\fR 121 .ad 122 .sp .6 123 .RS 4n 124 Enables \fBNFS\fR server logging for the specified file system. The optional 125 tag determines the location of the related log files. The \fBtag\fR is defined 126 in \fBetc/nfs/nfslog.conf\fR. If no \fBtag\fR is specified, the default values 127 associated with the \fBglobal\fR \fBtag\fR in \fBetc/nfs/nfslog.conf\fR is 128 used. Support of NFS server logging is only available for NFS Version 2 and 129 Version 3 requests. 130 .RE 131 132 .sp 133 .ne 2 134 .na 135 \fB\fBnone=\fR\fIaccess_list\fR\fR 136 .ad 137 .sp .6 138 .RS 4n 139 Access is not allowed to any client that matches the access list. The exception 140 is when the access list is an asterisk (\fB*\fR), in which case \fBro\fR or 141 \fBrw\fR can override \fBnone\fR. 142 .RE 143 144 .sp 145 .ne 2 146 .na 147 \fB\fBnosub\fR\fR 148 .ad 149 .sp .6 150 .RS 4n 151 Prevents clients from mounting subdirectories of shared directories. For 152 example, if \fB/export\fR is shared with the \fBnosub\fR option on server 153 \fIfooey\fR then a \fBNFS\fR client cannot do: 154 .sp 155 .in +2 156 .nf 157 mount -F nfs fooey:/export/home/mnt 158 .fi 159 .in -2 160 .sp 161 162 NFS Version 4 does not use the \fBMOUNT\fR protocol. The \fBnosub\fR option 163 only applies to NFS Version 2 and Version 3 requests. 164 .RE 165 166 .sp 167 .ne 2 168 .na 169 \fB\fBnosuid\fR\fR 170 .ad 171 .sp .6 172 .RS 4n 173 By default, clients are allowed to create files on the shared file system with 174 the setuid or setgid mode enabled. Specifying \fBnosuid\fR causes the server 175 file system to silently ignore any attempt to enable the setuid or setgid mode 176 bits. 177 .RE 178 179 .sp 180 .ne 2 181 .na 182 \fB\fBpublic\fR\fR 183 .ad 184 .sp .6 185 .RS 4n 186 Moves the location of the public file handle from \fBroot\fR (\fB/\fR) to the 187 exported directory for Web\fBNFS\fR-enabled browsers and clients. This option 188 does not enable Web\fBNFS\fR service; Web\fBNFS\fR is always on. Only one file 189 system per server may use this option. Any other option, including the 190 \fB-ro=list\fR and \fB-rw=list\fR options can be included with the \fBpublic\fR 191 option. 192 .RE 193 194 .sp 195 .ne 2 196 .na 197 \fB\fBro\fR\fR 198 .ad 199 .sp .6 200 .RS 4n 201 Sharing is read-only to all clients. 202 .RE 203 204 .sp 205 .ne 2 206 .na 207 \fB\fBro=\fR\fIaccess_list\fR\fR 208 .ad 209 .sp .6 210 .RS 4n 211 Sharing is read-only to the clients listed in \fIaccess_list\fR; overrides the 212 \fBrw\fR suboption for the clients specified. See \fIaccess_list\fR below. 213 .RE 214 215 .sp 216 .ne 2 217 .na 218 \fB\fBroot=\fR\fIaccess_list\fR\fR 219 .ad 220 .sp .6 221 .RS 4n 222 Only root users from the hosts specified in \fIaccess_list\fR have root access. 223 See \fIaccess_list\fR below. By default, no host has root access, so root users 224 are mapped to an anonymous user \fBID\fR (see the \fBanon=\fR\fIuid\fR option 225 described above). Netgroups can be used if the file system shared is using UNIX 226 authentication ( \fBAUTH_SYS\fR). 227 .RE 228 229 .sp 230 .ne 2 231 .na 232 \fB\fBroot_mapping=\fIuid\fR\fR\fR 233 .ad 234 .sp .6 235 .RS 4n 236 For a client that is allowed root access, map the root UID to the specified 237 user id. 238 .RE 239 240 .sp 241 .ne 2 242 .na 243 \fB\fBrw\fR\fR 244 .ad 245 .sp .6 246 .RS 4n 247 Sharing is read-write to all clients. 248 .RE 249 250 .sp 251 .ne 2 252 .na 253 \fB\fBrw=\fR\fIaccess_list\fR\fR 254 .ad 255 .sp .6 256 .RS 4n 257 Sharing is read-write to the clients listed in \fIaccess_list\fR; overrides the 258 \fBro\fR suboption for the clients specified. See \fIaccess_list\fR below. 259 .RE 260 261 .sp 262 .ne 2 263 .na 264 \fB\fBsec=\fR\fImode\fR[\fB:\fR\fImode\fR].\|.\|.\fR 265 .ad 266 .sp .6 267 .RS 4n 268 Sharing uses one or more of the specified security modes. The \fImode\fR in the 269 \fBsec=\fR\fImode\fR option must be a node name supported on the client. If the 270 \fBsec=\fR option is not specified, the default security mode used is 271 \fBAUTH_SYS.\fR Multiple \fBsec=\fR options can be specified on the command 272 line, although each mode can appear only once. The security modes are defined 273 in \fBnfssec\fR(5). 274 .sp 275 Each \fBsec=\fR option specifies modes that apply to any subsequent \fBwindow=, 276 rw, ro, rw=, ro=\fR and \fBroot=\fR options that are provided before another 277 \fBsec=\fRoption. Each additional \fBsec=\fR resets the security mode context, 278 so that more \fBwindow=,\fR \fBrw,\fR \fBro,\fR \fBrw=,\fR \fBro=\fR and 279 \fBroot=\fR options can be supplied for additional modes. 280 .RE 281 282 .sp 283 .ne 2 284 .na 285 \fB\fBsec=\fR\fInone\fR\fR 286 .ad 287 .sp .6 288 .RS 4n 289 If the option \fBsec=\fR\fInone\fR is specified when the client uses 290 \fBAUTH_NONE,\fR or if the client uses a security mode that is not one that the 291 file system is shared with, then the credential of each \fBNFS\fR request is 292 treated as unauthenticated. See the \fBanon=\fR\fIuid\fR option for a 293 description of how unauthenticated requests are handled. 294 .RE 295 296 .sp 297 .ne 2 298 .na 299 \fB\fBsecure\fR\fR 300 .ad 301 .sp .6 302 .RS 4n 303 This option has been deprecated in favor of the \fBsec=\fR\fIdh\fR option. 304 .RE 305 306 .sp 307 .ne 2 308 .na 309 \fB\fBwindow=\fR\fIvalue\fR\fR 310 .ad 311 .sp .6 312 .RS 4n 313 When sharing with \fBsec=\fR\fIdh\fR, set the maximum life time (in seconds) of 314 the \fBRPC\fR request's credential (in the authentication header) that the 315 \fBNFS\fR server allows. If a credential arrives with a life time larger than 316 what is allowed, the \fBNFS\fR server rejects the request. The default value is 317 30000 seconds (8.3 hours). 318 .RE 319 320 .RE 321 322 .SS "\fIaccess_list\fR" 323 .sp 324 .LP 325 The \fIaccess_list\fR argument is a colon-separated list whose components may 326 be any number of the following: 327 .sp 328 .ne 2 329 .na 330 \fBhostname\fR 331 .ad 332 .sp .6 333 .RS 4n 334 The name of a host. With a server configured for \fBDNS\fR or \fBLDAP\fR naming 335 in the \fBnsswitch\fR "hosts" entry, any hostname must be represented as a 336 fully qualified \fBDNS\fR or \fBLDAP\fR name. 337 .RE 338 339 .sp 340 .ne 2 341 .na 342 \fBnetgroup\fR 343 .ad 344 .sp .6 345 .RS 4n 346 A netgroup contains a number of hostnames. With a server configured for 347 \fBDNS\fR or \fBLDAP\fR naming in the \fBnsswitch\fR "hosts" entry, any 348 hostname in a netgroup must be represented as a fully qualified \fBDNS\fR or 349 \fBLDAP\fR name. 350 .RE 351 352 .sp 353 .ne 2 354 .na 355 \fBdomain name suffix\fR 356 .ad 357 .sp .6 358 .RS 4n 359 To use domain membership the server must use \fBDNS\fR or \fBLDAP\fR to resolve 360 hostnames to \fBIP\fR addresses; that is, the "hosts" entry in the 361 \fB/etc/nsswitch.conf\fR must specify "dns" or "ldap" ahead of "nis" or 362 "nisplus", since only \fBDNS\fR and \fBLDAP\fR return the full domain name of 363 the host. Other name services like \fBNIS\fR or \fBNIS+\fR cannot be used to 364 resolve hostnames on the server because when mapping an \fBIP\fR address to a 365 hostname they do not return domain information. For example, 366 .sp 367 .in +2 368 .nf 369 NIS or NIS+ 172.16.45.9 --> "myhost" 370 .fi 371 .in -2 372 .sp 373 374 and 375 .sp 376 .in +2 377 .nf 378 DNS or LDAP 172.16.45.9 --> 379 "myhost.mydomain.mycompany.com" 380 .fi 381 .in -2 382 .sp 383 384 The domain name suffix is distinguished from hostnames and netgroups by a 385 prefixed dot. For example, 386 .sp 387 \fBrw=.mydomain.mycompany.com\fR 388 .sp 389 A single dot can be used to match a hostname with no suffix. For example, 390 .sp 391 \fBrw=.\fR 392 .sp 393 matches "mydomain" but not "mydomain.mycompany.com". This feature can be used 394 to match hosts resolved through \fBNIS\fR and \fBNIS+\fR rather than \fBDNS\fR 395 and \fBLDAP\fR. 396 .RE 397 398 .sp 399 .ne 2 400 .na 401 \fBnetwork\fR 402 .ad 403 .sp .6 404 .RS 4n 405 The network or subnet component is preceded by an at-sign (\fB@\fR). It can be 406 either a name or a dotted address. If a name, it is converted to a dotted 407 address by \fBgetnetbyname\fR(3SOCKET). For example, 408 .sp 409 \fB=@mynet\fR 410 .sp 411 would be equivalent to: 412 .sp 413 \fB=@172.16\fR or \fB=@172.16.0.0\fR 414 .sp 415 The network prefix assumes an octet-aligned netmask determined from the zeroth 416 octet in the low-order part of the address up to and including the high-order 417 octet, if you want to specify a single IP address (see below). In the case 418 where network prefixes are not byte-aligned, the syntax allows a mask length to 419 be specified explicitly following a slash (\fB/\fR) delimiter. For example, 420 .sp 421 \fB=@theothernet/17\fR or \fB=@172.16.132/22\fR 422 .sp 423 \&...where the mask is the number of leftmost contiguous significant bits in 424 the corresponding IP address. 425 .sp 426 When specifying individual IP addresses, use the same \fB@\fR notation 427 described above, without a netmask specification. For example: 428 .sp 429 .in +2 430 .nf 431 =@172.16.132.14 432 .fi 433 .in -2 434 .sp 435 436 Multiple, individual IP addresses would be specified, for example, as: 437 .sp 438 .in +2 439 .nf 440 root=@172.16.132.20:@172.16.134.20 441 .fi 442 .in -2 443 .sp 444 445 .RE 446 447 .sp 448 .LP 449 A prefixed minus sign (\fB\(mi\fR) denies access to that component of 450 \fIaccess_list\fR. The list is searched sequentially until a match is found 451 that either grants or denies access, or until the end of the list is reached. 452 For example, if host "terra" is in the "engineering" netgroup, then 453 .sp 454 .in +2 455 .nf 456 rw=-terra:engineering 457 .fi 458 .in -2 459 .sp 460 461 .sp 462 .LP 463 denies access to \fBterra\fR but 464 .sp 465 .in +2 466 .nf 467 rw=engineering:-terra 468 .fi 469 .in -2 470 .sp 471 472 .sp 473 .LP 474 grants access to \fBterra\fR. 475 .SH OPERANDS 476 .sp 477 .LP 478 The following operands are supported: 479 .sp 480 .ne 2 481 .na 482 \fB\fIpathname\fR\fR 483 .ad 484 .sp .6 485 .RS 4n 486 The pathname of the file system to be shared. 487 .RE 488 489 .SH EXAMPLES 490 .LP 491 \fBExample 1 \fRSharing A File System With Logging Enabled 492 .sp 493 .LP 494 The following example shows the \fB/export\fR file system shared with logging 495 enabled: 496 497 .sp 498 .in +2 499 .nf 500 example% \fBshare -o log /export\fR 501 .fi 502 .in -2 503 .sp 504 505 .sp 506 .LP 507 The default global logging parameters are used since no tag identifier is 508 specified. The location of the log file, as well as the necessary logging work 509 files, is specified by the global entry in \fB/etc/nfs/nfslog.conf\fR. The 510 \fBnfslogd\fR(1M) daemon runs only if at least one file system entry in 511 \fB/etc/dfs/dfstab\fR is shared with logging enabled upon starting or rebooting 512 the system. Simply sharing a file system with logging enabled from the command 513 line does not start the \fBnfslogd\fR(1M). 514 515 .SH EXIT STATUS 516 .sp 517 .LP 518 The following exit values are returned: 519 .sp 520 .ne 2 521 .na 522 \fB\fB0\fR\fR 523 .ad 524 .sp .6 525 .RS 4n 526 Successful completion. 527 .RE 528 529 .sp 530 .ne 2 531 .na 532 \fB\fB>0\fR\fR 533 .ad 534 .sp .6 535 .RS 4n 536 An error occurred. 537 .RE 538 539 .SH FILES 540 .sp 541 .ne 2 542 .na 543 \fB\fB/etc/dfs/fstypes\fR\fR 544 .ad 545 .sp .6 546 .RS 4n 547 list of system types, \fBNFS\fR by default 548 .RE 549 550 .sp 551 .ne 2 552 .na 553 \fB\fB/etc/dfs/sharetab\fR\fR 554 .ad 555 .sp .6 556 .RS 4n 557 system record of shared file systems 558 .RE 559 560 .sp 561 .ne 2 562 .na 563 \fB\fB/etc/nfs/nfslogtab\fR\fR 564 .ad 565 .sp .6 566 .RS 4n 567 system record of logged file systems 568 .RE 569 570 .sp 571 .ne 2 572 .na 573 \fB\fB/etc/nfs/nfslog.conf\fR\fR 574 .ad 575 .sp .6 576 .RS 4n 577 logging configuration file 578 .RE 579 580 .SH SEE ALSO 581 .sp 582 .LP 583 \fBmount\fR(1M), \fBmountd\fR(1M), \fBnfsd\fR(1M), \fBnfslogd\fR(1M), 584 \fBshare\fR(1M), \fBunshare\fR(1M), \fBgetnetbyname\fR(3SOCKET), 585 \fBnfslog.conf\fR(4), \fBnetgroup\fR(4), \fBattributes\fR(5), \fBnfssec\fR(5) 586 .SH NOTES 587 .sp 588 .LP 589 If the \fBsec=\fR option is presented at least once, all uses of the 590 \fBwindow=,\fR \fBrw,\fR \fBro,\fR \fBrw=,\fR \fBro=\fR and \fBroot=\fR options 591 must come \fBafter\fR the first \fBsec=\fR option. If the \fBsec=\fR option is 592 not presented, then \fBsec=\fR\fIsys\fR is implied. 593 .sp 594 .LP 595 If one or more explicit \fBsec=\fR options are presented, \fIsys\fR must appear 596 in one of the options mode lists for accessing using the \fBAUTH_SYS\fR 597 security mode to be allowed. For example: 598 .sp 599 .in +2 600 .nf 601 \fBshare\fR \fB-F\fR \fBnfs /var\fR 602 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBsec=sys /var\fR 603 .fi 604 .in -2 605 .sp 606 607 .sp 608 .LP 609 grants read-write access to any host using \fBAUTH_SYS,\fR but 610 .sp 611 .in +2 612 .nf 613 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBsec=dh /var\fR 614 .fi 615 .in -2 616 .sp 617 618 .sp 619 .LP 620 grants no access to clients that use \fBAUTH_SYS.\fR 621 .sp 622 .LP 623 Unlike previous implementations of \fBshare_nfs\fR, access checking for the 624 \fBwindow=, rw, ro, rw=,\fR and \fBro=\fR options is done per \fBNFS\fR 625 request, instead of per mount request. 626 .sp 627 .LP 628 Combining multiple security modes can be a security hole in situations where 629 the \fBro=\fR and \fBrw=\fR options are used to control access to weaker 630 security modes. In this example, 631 .sp 632 .in +2 633 .nf 634 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBsec=dh,rw,sec=sys,rw=hosta /var\fR 635 .fi 636 .in -2 637 .sp 638 639 .sp 640 .LP 641 an intruder can forge the IP address for \fBhosta\fR (albeit on each \fBNFS\fR 642 request) to side-step the stronger controls of \fBAUTH_DES.\fR Something like: 643 .sp 644 .in +2 645 .nf 646 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBsec=dh,rw,sec=sys,ro /var\fR 647 .fi 648 .in -2 649 .sp 650 651 .sp 652 .LP 653 is safer, because any client (intruder or legitimate) that avoids 654 \fBAUTH_DES\fR only gets read-only access. In general, multiple security modes 655 per \fBshare\fR command should only be used in situations where the clients 656 using more secure modes get stronger access than clients using less secure 657 modes. 658 .sp 659 .LP 660 If \fBrw=,\fR and \fBro=\fR options are specified in the same \fBsec=\fR 661 clause, and a client is in both lists, the order of the two options determines 662 the access the client gets. If client \fBhosta\fR is in two netgroups - 663 \fBgroup1\fR and \fBgroup2\fR - in this example, the client would get read-only 664 access: 665 .sp 666 .in +2 667 .nf 668 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBro=group1,rw=group2 /var\fR 669 .fi 670 .in -2 671 .sp 672 673 .sp 674 .LP 675 In this example \fBhosta\fR would get read-write access: 676 .sp 677 .in +2 678 .nf 679 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBrw=group2,ro=group1 /var\fR 680 .fi 681 .in -2 682 .sp 683 684 .sp 685 .LP 686 If within a \fBsec=\fR clause, both the \fBro\fR and \fBrw=\fR options are 687 specified, for compatibility, the order of the options rule is not enforced. 688 All hosts would get read-only access, with the exception to those in the 689 read-write list. Likewise, if the \fBro=\fR and \fBrw\fR options are specified, 690 all hosts get read-write access with the exceptions of those in the read-only 691 list. 692 .sp 693 .LP 694 The \fBro=\fR and \fBrw=\fR options are guaranteed to work over \fBUDP\fR and 695 \fBTCP\fR but may not work over other transport providers. 696 .sp 697 .LP 698 The \fBroot=\fR option with \fBAUTH_SYS\fR is guaranteed to work over \fBUDP\fR 699 and \fBTCP\fR but may not work over other transport providers. 700 .sp 701 .LP 702 The \fBroot=\fR option with \fBAUTH_DES\fR is guaranteed to work over any 703 transport provider. 704 .sp 705 .LP 706 There are no interactions between the \fBroot=\fR option and the \fBrw, ro, 707 rw=,\fR and \fBro=\fR options. Putting a host in the \fBroot\fR list does not 708 override the semantics of the other options. The access the host gets is the 709 same as when the \fBroot=\fR options is absent. For example, the following 710 \fBshare\fR command denies access to \fBhostb:\fR 711 .sp 712 .in +2 713 .nf 714 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBro=hosta,root=hostb /var\fR 715 .fi 716 .in -2 717 .sp 718 719 .sp 720 .LP 721 The following gives read-only permissions to \fBhostb:\fR 722 .sp 723 .in +2 724 .nf 725 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBro=hostb,root=hostb /var\fR 726 .fi 727 .in -2 728 .sp 729 730 .sp 731 .LP 732 The following gives read-write permissions to \fBhostb:\fR 733 .sp 734 .in +2 735 .nf 736 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBro=hosta,rw=hostb,root=hostb /var\fR 737 .fi 738 .in -2 739 .sp 740 741 .sp 742 .LP 743 If the file system being shared is a symbolic link to a valid pathname, the 744 canonical path (the path which the symbolic link follows) are shared. For 745 example, if \fB/export/foo\fR is a symbolic link to \fB/export/bar\fR 746 (\fB/export/foo -> /export/bar\fR), the following \fBshare\fR command results 747 in \fB/export/bar\fR as the shared pathname (and not \fB/export/foo\fR). 748 .sp 749 .in +2 750 .nf 751 \fBexample# share\fR \fB-F\fR \fBnfs /export/foo\fR 752 .fi 753 .in -2 754 .sp 755 756 .sp 757 .LP 758 An \fBNFS\fR mount of \fBserver:/export/foo\fR results in 759 \fBserver:/export/bar\fR really being mounted. 760 .sp 761 .LP 762 This line in the \fB/etc/dfs/dfstab\fR file shares the \fB/disk\fR file system 763 read-only at boot time: 764 .sp 765 .in +2 766 .nf 767 \fBshare\fR \fB-F\fR \fBnfs\fR \fB-o\fR \fBro /disk\fR 768 .fi 769 .in -2 770 .sp 771 772 .sp 773 .LP 774 The same command entered from the command line does not share the \fB/disk\fR 775 file system unless there is at least one file system entry in the 776 \fB/etc/dfs/dfstab\fR file. The \fBmountd\fR(1M) and \fBnfsd\fR(1M) daemons 777 only run if there is a file system entry in \fB/etc/dfs/dfstab\fR when starting 778 or rebooting the system. 779 .sp 780 .LP 781 The \fBmountd\fR(1M) process allows the processing of a path name the contains 782 a symbolic link. This allows the processing of paths that are not themselves 783 explicitly shared with \fBshare_nfs\fR. For example, \fB/export/foo\fR might be 784 a symbolic link that refers to \fB/export/bar\fR which has been specifically 785 shared. When the client mounts \fB/export/foo\fR the \fBmountd\fR processing 786 follows the symbolic link and responds with the \fB/export/bar\fR. The NFS 787 Version 4 protocol does not use the \fBmountd\fR processing and the client's 788 use of \fB/export/foo\fR does not work as it does with NFS Version 2 and 789 Version 3 and the client receives an error when attempting to mount 790 \fB/export/foo\fR.