2 .\" ===================================
3 .\" HARP | Host ATM Research Platform
4 .\" ===================================
7 .\" This Host ATM Research Platform ("HARP") file (the "Software") is
8 .\" made available by Network Computing Services, Inc. ("NetworkCS")
9 .\" "AS IS". NetworkCS does not provide maintenance, improvements or
10 .\" support of any kind.
12 .\" NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
13 .\" INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
14 .\" AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
15 .\" SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
16 .\" In no event shall NetworkCS be responsible for any damages, including
17 .\" but not limited to consequential damages, arising from or relating to
18 .\" any use of the Software or related support.
20 .\" Copyright 1994-1998 Network Computing Services, Inc.
22 .\" Copies of this Software may be made, however, the above copyright
23 .\" notice must be reproduced on all copies.
35 .Op Fl f Aq Ar cfg\-file
37 .Op Fl T Ns Aq Ar options
41 utility is an implementation of the Server Cache Synchronization
42 Protocol (SCSP) for the Host ATM Research Platform (HARP)
46 utility synchronizes the cache(s) of server(s)
47 running on a host with the caches of servers on remote hosts.
48 SCSP is defined for a number of different protocols, but the present
57 one can provide multiple
58 ATMARP servers in a single ATM LIS.
59 This might be useful, for example, when a LIS consists of a number of
60 local-area ATM networks connected by long-distance links.
61 Each local-area network could have its own ATMARP server, with all the
62 servers' caches being synchronized by SCSP.
63 Then, if a long-distance link fails, hosts on a local-area network
64 will still have connectivity to other local hosts (since they all use
65 the local ATMARP server); when the long-distance link is restored,
66 SCSP will re-synchronize the servers' caches, restoring
67 connectivity to remote hosts.
72 must be running before any ATMARP
73 cache synchronization can take place.
77 utility implements SCSP as specified in RFC 2334,
78 .%T "Server Cache Synchronization Protocol (SCSP)"
80 .Pa draft\-ietf\-ion\-scspd\-atmarpd\-00.txt ,
81 .%T "A Distributed ATMARP Service using SCSP" .
85 starts, it parses its command line and puts
86 itself into the background.
88 Some of the vocabulary associated with SCSP can be confusing.
89 In this document, the following definitions are used:
94 means the server running on
97 whose cache is to be synchronized with that
98 of one or more remote servers.
101 is used alone, it means
102 .Em "client server" .
105 means a server running on some host other than
110 .Em "Directly Connected Server"
111 (DCS) means a remote server that
113 communicates with directly.
114 The remote server will also be running an implementation of SCSP.
116 .Em "Cache Alignment"
117 (CA) has two meanings.
118 The Cache Alignment protocol is a part of the SCSP protocol
119 specification, and the Cache Alignment finite state machine (FSM)
120 is a finite state machine that implements the Cache Alignment
123 The command-line options are:
124 .Bl -tag -width "-f <cfg\-file>"
125 .It Fl f Aq Ar cfg\-file
126 Specifies the name of the configuration file.
127 If this option is not specified,
131 .Pa /etc/scspd.conf .
135 is to be run in debug mode.
136 In debug mode, the daemon is not put into the background.
137 Log messages are written to standard output instead of to
138 the log file specified in the configuration file.
139 .It Fl T Ns Aq Ar options
142 will trace specified events and messages
146 flag is followed by one or more of the following
149 .Bl -tag -width 4n -compact
153 CA Finite State Machine (FSM),
161 Client Interface FSM,
163 trace CA, CSUS, CSU Request, and CSU Reply messages,
165 trace Hello messages,
167 trace interface messages to and from
173 The configuration file consists of a sequence of configuration
175 These statements specify information about the servers,
176 both local and remote, whose
177 caches are to be synchronized by
180 .%T "Server Cache Synchronization Protocol (SCSP)"
182 .Pa draft\-ietf\-ion\-scspd\-atmarpd\-00.txt ,
183 .%T "A Distributed ATMARP Service using SCSP"
184 will be valuable in understanding how to configure
187 A configuration statement other than a comment is terminated by a
189 Some statements contain blocks, delimited by braces
193 Configuration statement keywords are not case-sensitive,
194 but some parameters (e.g.\& interface names) are.
195 Configuration statements can span multiple lines.
197 Three types of comments are allowed:
199 .It Sy "# comments" :
202 to the end of the line are ignored.
203 .It Sy "C comments" :
204 any characters between
209 .It Sy "C++ comments" :
212 to the end of the line are ignored.
215 The configuration statements recognized by
220 Protocol <protocol ID>;
225 ATMaddr <ATM address>;
243 Where a host address needs to be specified in the configuration file,
244 either a DNS name or an IP address in dotted decimal format can
247 ATM addresses are specified as strings of hex digits, with an
250 Fields within the address may be separated by periods, but periods
251 are for readability only and are ignored.
252 ATM addresses are 20 bytes long.
253 The full address, including any leading zeroes, must be given.
256 .Dl "0x47.0005.80.ffe100.0000.f21a.0170.0020481a0170.00"
257 .Ss "Server Statement"
260 statement specifies a client server whose cache
261 to be synchronized with the caches of other servers
262 running on remote hosts.
265 statement in the configuration file
266 for each client server whose cache is to be synchronized by
271 .Bd -ragged -offset indent
281 must be specified on the
286 It is expected to give a brief description of the server's purpose.
290 statement has several sub-statements
291 that specify the details of the
295 .Bl -tag -width indent
296 .It Ic Protocol Cm ATMARP ;
297 The only protocol supported by the current version of
303 statement must always be specified.
304 .It Ic Netif Aq Ar intf ;
307 statement specifies the name of the ATM network
308 interface on which a client server is providing service.
311 statement must always be specified.
312 .It Ic ServerGroupID Aq Ar ID ;
315 statement specifies an identifier for the
316 group of servers being synchronized by
320 is specified as a decimal number in the range 0 - 65,535.
321 The server group ID must be the same for all servers whose caches
322 are being synchronized by an SCSP session.
323 That is, the server group ID for a host must be the same for all
324 Directly Connected Servers (DCSs) pointed to within a
329 statement must always be specified.
330 .It Ic FamilyID Aq Ar ID ;
333 statement specifies an identifier for a family
334 of parallel SCSP sessions running between a group of hosts (i.e., a
335 set of SCSP sessions with different protocol IDs but the same set
339 is specified as a decimal number in the range 0 - 65,535.
340 The family ID is currently not used by
346 statement is a sub-statement of the
349 that specifies the characteristics of a Directly Connected Server (DCS).
352 statement will have one
357 is to exchange information with.
360 statement has a number of sub-statements that specify the
361 details of the configuration for the DCS.
363 .Bl -tag -width indent
364 .It Ic ATMaddr Aq Ar ATM\ address ;
367 statement specifies the ATM address of the DCS.
370 statement must always be specified.
371 .It Ic ID Aq Ar host ;
374 statement specifies the SCSP identifier of the DCS.
375 For ATMARP, the ID is the IP address or DNS name associated with the
376 ATM interface of the DCS.
379 statement must always be specified.
380 .It Ic CAReXmitInt Aq Ar int ;
383 statement specifies the interval that is
384 allowed to elapse between retransmissions of CA messages.
385 If a CA message is sent and an acknowledgement is not received within
387 seconds, the message will be retransmitted.
388 The default value for
391 .It Ic CSUSReXmitInt Aq Ar int ;
394 statement specifies the interval that is
395 allowed to elapse between retransmissions of CSU Solicit messages.
396 When a CSUS message is sent, any Cache State Advertisements (CSAs)
397 requested by the CSUS that have
398 not been received within
400 seconds will be requested
401 again by another CSUS message.
402 The default value for
405 Be careful not to confuse
409 .It Ic CSUReXmitInt Aq Ar int ;
412 statement specifies the interval that is
413 allowed to elapse between retransmissions of CSU Request messages.
414 When a CSU Request message is sent, any CSAs that are not acknowledged
415 by a CSU Reply message within
419 The default value for
422 Be careful not to confuse
426 .It Ic CSUReXmitMax Aq Ar cnt ;
429 statement specifies the number of times that
430 a CSA will be retransmitted as described above before SCSP gives up
431 on the CSA and discards it.
432 The default value for
435 .It Ic HelloDead Aq Ar cnt ;
438 statement specifies the Hello Dead Factor that
439 will be sent to the DCS in Hello messages.
442 condition will be detected when nothing is received from
444 .Ic HelloDead No * Ic HelloInt
446 The default value for
449 .It Ic HelloInt Aq Ar int ;
452 statement specifies the Hello Interval that
453 will be sent to the DCS in Hello messages.
454 The default value for
457 .It Ic Hops Aq Ar cnt ;
460 statement specifies the number of hops (DCS to DCS)
461 that will be specified in CSAs originating from the local server.
462 This number must be at least as large as the diameter of the
464 That is, it must be large enough for a CSA to be propagated from
465 server to server all the way across the server group.
466 The default value for
473 statement specifies how
476 information about its operation.
479 utility can write log information to a file, to the system log,
481 .Bl -tag -width indent
482 .It Ic File Aq Ar file\ name ;
485 statement specifies that
488 its log messages to the named file.
489 Log messages will be appended to the end of the file if
494 statement specifies that
497 its log messages to the syslog facility.
500 utility writes its messages to syslog with a facility code
507 statement is specified,
510 messages to the system log.
518 write log messages to both the named file and the system log.
520 An example of a simple configuration file for
523 .Bd -literal -offset indent
530 ATMaddr 0x47.0005.80.ffdc00.0000.0002.0001.002048061de7.00;
536 This configuration would synchronize the cache of the ATMARP server
537 operating on network interface ni0 with the cache of a second server
538 running on a host whose IP address is 10.1.1.2.
539 Log messages would be written to the system log.
540 .Sh SIGNAL PROCESSING
541 The following signals can be used to control
543 .Bl -tag -width indent
545 Reread the configuration file and restart
548 Dump debugging information to a file.
554 its control blocks to a text file (see
558 .Bl -tag -width indent
559 .It Pa /etc/scspd.conf
561 default configuration file name.
562 A different file name can be specified with the
575 debugging information dump file name.
578 utility writes a summary of its control blocks to this file
583 is the process ID of the daemon and
586 number which is incremented every time a dump is taken.
597 utility writes trace information to this file if the
599 option is specified on the command line.
606 .%T "Server Cache Synchronization Protocol (SCSP)"
609 .%O "draft\-ietf\-ion\-scsp\-atmarpd\-00.txt"
610 .%T "A Distributed ATMARP Service Using SCSP"
613 Copyright (c) 1994-1998, Network Computing Services, Inc.
616 Network Computing Services, Inc.
618 Network Computing Services, Inc.
620 Network Computing Services, Inc.
622 This software was developed with the support of the Defense
623 Advanced Research Projects Agency (DARPA).
627 terminates and is restarted, there will be a period of
628 instability while previously-synchronized cache entries time out and are
631 Please report any bugs to
632 .Aq harp\-bugs@magic.net .