There are a couple of configuration variables that are common to all modules. The documentation for these can be found in the svxlink.conf(5) manual page.
Here is the description of all module specific configuration variables that the SvxLink EchoLink module understands.
- Use this variable very carefully. Connections originating from the given subnet will not be checked against the EchoLink directory server. A typical use of this is if you want to connect to your own svxlink server and both the server and you are behind a IP masquerading firewall.
- Drop all incoming connections where the remote callsign match this regular expression. No message will be sent to the remote station notifying about the drop. The connection will just be ignored. For more information on the syntax, see the Regular Expressions chapter below.
- Reject all incoming connections where the remote callsign match this regular expression. A message will be sent to the remote station indicating that the connection was rejected. The DROP_INCOMING directive will be evaluated before REJECT_INCOMING. For more information on the syntax, see the Regular Expressions chapter below.
- Only accept incoming connections where the remote callsign match this regular expression. If the callsign doesn't match, a message will be sent to the remote station indicating that the connection was rejected. The DROP_INCOMING and REJECT_INCOMING directives will be evaluated before ACCEPT_INCOMING. For more information on the syntax, see the Regular Expressions chapter below.
- Reject all outgoing connections where the remote callsign match this regular expression. For more information on the syntax, see the Regular Expressions chapter below.
- When this is set to 1, reject all incoming connections where the name of the remote station ends in the word CONF. A message will be sent to the remote station indicating that the connection was rejected. This blocks connects from stations that are in conference mode. When a station enters conference mode after connecting, and transmits towards us, it will be disconnected as well.
- If a station connects to often it can be blocked for a configurable time span. Example: CHECK_NR_CONNECTS=3,300,120 If a station connects more than 3 times with less than 300 seconds in between each connect, that station will be rejected for 120 minutes.
- Only accept outgoing connections where the remote callsign match this regular expression. The REJECT_OUTGOING directive will be evaluated before ACCEPT_OUTGOING. For more information on the syntax, see the Regular Expressions chapter below.
- A space separated list of IP addresses or names of the EchoLink directory servers to use. The specified servers will be tried in order until one is found that works. SvxLink will then stick to that server. If that server fail, SvxLink will again try the next server in the list and when the end of the list has been reached, the search start from the beginning again. Hostnames that resolve to multiple IP addresses, like servers.echolink.org, will also be correctly handled so that all returned IP addresses will be tried if necessary.
- The callsign to use to login to the EchoLink directory server.
- The name of the person or club that is responsible for this system.
- The EchoLink directory server password to use.
- The location of the station. Note: In the default configuration file the value of this configuration variable starts with "[Svx]". This is of course not necessary but it's fun to see which other stations are running SvxLink.
- If set, connect to the given EchoLink proxy server host. All EchoLink connections, both incoming and outgoing, will then go through the proxy.
- Set the TCP port used for connecing to an EchoLink proxy server. Default is 8100.
- Set the EchoLink proxy password used when connecting to an EchoLink proxy server. Use the password PUBLIC for public proxy servers.
This configuration variable can be set to bind the EchoLink network sockets to a specific IP-address/interface. This may be needed if the computer is fitted with more than one ethernet interface and EchoLink should only be used on one of them.
- The maximum number of stations that can participate in a conference QSO on this node. If more stations try to connect, the connect request will be rejected.
- On smaller systems with a less powerful CPU it is a good idea to prevent SvxLink from switching into the Speex codec when another SvxLink station is connecting via EchoLink. If this param is set to 1 SvxLink remains in the default codec (GSM).
- Set the language to use for announcements sent to remote EchoLink stations. If not set, it will be the same as the one chosen for the logic core. The reason for setting this up may be that you want one language for the core and another language for annoncements sent to remote EchoLink stations.
- When more stations than specified in MAX_QSOS try to connect, a connection will temporarily be established long enough to play a message telling the remote station that the connection was rejected. The connection is then immediately terminated. If the number of connections exceeds MAX_CONNECTIONS, the connect request is just ignored. This variable is typically set to MAX_QSOS+1 or more if using a large number for MAX_QSOS.
- The number of seconds that a connection is idle before disconnection will occur. This is to prevent a link to stay open if someone forget to disconnect. Disable this feature by setting this config variable to zero (or comment it out).
- Set this variable to an EchoLink ID that you want to automatically connect to. SvxLink will autoconnect only when no other station is connected.
- Set this to the time in seconds that you want in between autoconnect tries.
- A longer description that is sent to remote stations upon connection. This description should typically include detailed station information like QTH, transceiver frequency/power, antenna, CTCSS tone frequency etc.
Regular expressions are used in the DROP, REJECT and ACCEPT configuration variables. A regular expression can be quite complex and the syntax is fully described in the regex(7) manual page. This is just a quick tutorial for the most important features.
- match the beginning of a string.
- match the end of a string.
- match one character.
- match the previous expression zero or more times.
- match the expression before OR after the |.
- escape the following character. Note that backslash is also parsed by the SvxLink configuration parser so a backslash must actually be typed as two. For example to include a * in the matching pattern it must be escaped as \\*.
- grouping an expression.
- match any of the characters inside of the brackets.
- Match AB1CDE or BA5CBA-L.
- Match AB1CDE-L or AB1CDR-R.
- Match all callsigns starting with AB1.
- Match all conference "callsigns". We need to escape the star character since it would otherwise be parsed by the regular expression parser. We also need two backslah characters so that the SvxLink configuration reader doesn't parse it as an escape sequence.
The matches in SvxLink are case insensitive so "sm3" and "SM3" are the same. SvxLink use extended regular expressions (see regex(7) ). You almost always want to start the regular expression with "^(" and end it with ")$" so that the whole callsign will be used in the match.