slp.conf(4) Kernel Interfaces Manual slp.conf(4)
NAME
slp.conf - configuration file for SLP agents
SYNOPSIS
DESCRIPTION
The file contains various configuration options for the agents which include the clients that use SLP APIs, the Service Agent server and
Directory agents. It determines the configuration of all the SLP agents running on that host.
The SLP SA server and DA read the file during their invocation and also when they are reconfigured by sending the signal. The properties
specified in the configuration file are read into process memory.
Later modifications to this configuration file do not affect the operation of already running agents unless they are reconfigured or
restarted.
The configuration file is read by the SLP APIs whenever invoked by "UAs" to determine the value of configuration parameters specified in
the configuration file which are used by the APIs when sending queries.
The configuration file format consists of a newline delimited list of zero or more property definitions. Each property definition corre-
sponds to a particular configurable SLP, network, or other parameter in one or more of the three SLP agents. The file format grammar in
ABNF [5] syntax is:
config-file = line-list
line-list = line / line line-list
line = property-line / comment-line
comment-line = ( "#" / ";" ) 1*allchar newline
property-line = property newline
property = tag "=" value-list
tag = prop / prop "." tag
prop = 1*tagchar
value-list = value / value "," value-list
value = int / bool /
"(" value-list ")" / string
int = 1*DIGIT
bool = "true" / "false" / "TRUE" / "FALSE"
newline = CR / ( CRLF )
string = 1*stringchar
tagchar = DIGIT / ALPHA / tother / escape
tother = %x21-%x2d / %x2f /
%x3a / %x3c-%x40 /
%x5b-%x60 / %7b-%7e
; i.e., all characters except `.',
; and `='.
stringchar = DIGIT / ALPHA / sother / escape
sother = %x21-%x29 / %x2a-%x2b /
%x2d-%x2f / %x3a-%x40 /
%x5b-%x60 / %7b-%7e
; i.e., all characters except `,'
allchar = DIGIT / ALPHA / HTAB / SP
escape = "
; Used for reserved characters
The configuration properties break down into the following categories:
DA Configuration
Static Scope Configuration
Tracing and Logging
Serialized Proxy Registrations
Networking Configuration Parameters
UA Configuration
The following sections of configuration properties are specified in RFC2614 and are supported for the above categories.
DA configuration
The configuration properties for DAs are explained in this section.
A boolean indicating if the SLP server is to act as a DA.
If false, slpd runs as SA server. Default is false.
A 32 bit integer giving the number of seconds for the DA
heartbeat. The default is 3 hours (10800 seconds). This value is ignored if isDA is false.
A comma-separated list of parenthesized attribute/value list
pairs that the DA must advertise in DAAdverts. The property must be in the SLP attribute list wire format, including escapes for
reserved characters. This property is currently ignored.
Static Scope Configuration
These properties allow various aspects of scope handling to be configured.
A value-list of strings indicating the scopes that a UA or SA
is allowed to use while making requests or registrations, or the scopes that a DA must support. In the absence of a DA and SA or no
scope information is available from DHCP, the default scope "DEFAULT" is used. If this parameter is not specified in the UA or no
scope information is available from DHCP, then the user scoping model will be used. The UA can give available information on all
the scopes to be used through active or passive DA or SA discovery. If this information cannot be discovered here, then the scope
"DEFAULT" is used. Unlike the other properties, this property is "read-only". Hence, any attempts to change this setting after the
configuration file has been read are ignored.
A value-list of IP addresses or DNS resolvable host names
of SLPv2 DAs that has to be used by statically configured UAs and SAs for sending queries and registrations. This value-list is
ignored by DAs (unless the DA is also an SA server). Default is none. Unlike the other properties, this property is "read-only".
Hence, any attempts to change it after the configuration file has been read are ignored.
The following grammar describes the property:
addr-list = addr / addr "," addr-list
addr = fqdn / hostnumber
fqdn = ALPHA / ALPHA *[ anum / "-" ] anum
anum = ALPHA / DIGIT
hostnumber = 1*3DIGIT 3("." 1*3DIGIT)
An example is:
IP addresses can be used instead of host names in networks where DNS is not deployed, but network administrators are reminded that
using IP addresses will complicate machine renumbering, since the SLP configuration property files in statically configured net-
works will have to be changed. Similarly, if host names are used, implementors must be careful that a name service is available
before SLP starts. In other words, SLP cannot be used to find the name service.
Tracing and Logging
This section describes tracing and logging information to be printed by the various agents.
A boolean controlling printing of messages about traffic with
DAs. Default is false.
A boolean controlling printing of details on SLP messages.
The fields in all incoming messages and outgoing replies are printed. Default is false.
A boolean controlling printing of details when a SLP message is
dropped for any reason. Default is false.
A boolean controlling dumps of all registered services upon
registration and deregistration. If true, the contents of the DA or SA server are dumped after a registration or deregistration
occurs. Default is false.
Network Configuration Properties
The properties in this section allow various network configuration properties to be set.
A boolean indicating if broadcast should be used instead of
multicast. This setting is seldom necessary since SLP will automatically use broadcast if multicast is unavailable. Default is
false.
A boolean indicating whether passive DA detection should be
used. Default is true.
A positive integer less than or equal to 255, giving the
multicast TTL. Default is 255.
A 16 bit positive integer giving the number of seconds between
DA active discovery queries. Default is 900 seconds (15 minutes). If the property is set to zero, active discovery is turned off.
This is useful when the DAs available are explicitly restricted to those obtained from or the property.
A 32 bit integer giving the maximum amount of time to perform
multicast, in milliseconds. Default is 15000 ms (15 sec).
Currently this parameter value is not being used.
Currently multicast timeouts are generated internally based on the net.slp.multicastMaximumWait parameter.
Currently this parameter value is not being used.
Currently multicast timeouts are generated internally based on the net.slp.multicastMaximumWait parameter.
Currently this parameter value is not being used.
Currently multicast timeouts are generated internally based on the net.slp.unicastMaximumWait parameter.
A 32 bit integer giving the maximum value for all random
wait parameters, in milliseconds. Default is 1000 ms (1 second).
A 16 bit integer giving the network packet MTU, in bytes.
This is the maximum size of any datagram to send, but the implementation might receive a larger datagram. The maximum size includes
IP, and UDP or TCP headers. Default is 1400 bytes.
Value-list of strings giving the IP addresses of network
interfaces on which the DA or SA should listen on port 427 for multicast, unicast UDP, and TCP messages. The default is to use all
the network interfaces.
An example is:
The example machine has three interfaces on which the DA should listen.
Note that since this property only takes IP addresses, it will need to be changed if the network is renumbered.
SA Configuration
This section describes the configuration properties for the SA. These properties are typically set programmatically by the SA, since they
are specific to each SA.
A comma-separated list of parenthesized attribute/value list
pairs that the SA must advertise in SAAdverts. The property must be in the SLP attribute list wire format, including escapes for
reserved characters.
Currently this property is ignored.
UA Configuration
This section describes configuration properties for the UA. These properties can be set either programmatically by the UA or in the con-
figuration file.
An RFC 1766 Language Tag for the language locale.
Setting this property causes the property value to become the default locale for SLP messages. Default is "en". This property is
also used for SA and DA configuration.
Currently only "en" (English) language is recognized and any other language tag is ignored.
A 32 bit integer giving the maximum number of results to
accumulate and return for a synchronous request before the timeout, or the maximum number of results to return through a callback if
the request results are reported asynchronously.
DAs and SAs always return all results that match the request. This configuration value applies only to UAs, that filter incoming
results and only return as many values as net.slp.maxResults indicates.
A value-list of service type names.
In the absence of any DAs, UAs perform SA discovery for finding scopes. These SA discovery requests may contain a request for ser-
vice types as an attribute.
The API implementation will use the service type names supplied by this property to discover only those SAs (and their scopes) which
support the desired service type or types. For example, if net.slp.typeHint is set to "service:imap,service:pop3" then SA discovery
requests will include the search filter:
The API library can also use unicast to contact the discovered SAs for subsequent requests for these service types, to optimize net-
work access.
Indicates whether all agents should use authentication blocks.
Currently ignored.
AUTHOR
was developed by Caldera Systems, Inc.
SEE ALSO
slpd(1M), slp.reg(4).
RFC 2614, RFC 2608.
slp.conf(4)