As stated previously, the aim of this document is not to tell you how to configure Linux or the ax25 utilities. However, -you do need to add a line in your ax25d.conf to allow connections to DXSpider for your users. For each interface that -you wish to allow connections on, use the following format ... +
Upto v1.44 it was not possible for the user to set their own filters. From +v1.45 though that has all changed. It is now possible to set filters for just +about anything you wish. If you have just updated from an older version of +DXSpider you will need to update your new filters. You do not need to do +anything with your old filters, they will be renamed as you update.
-
-
-default * * * * * * - sysop /spider/src/client client %u ax25
-
-There are 3 basic commands involved in setting and manipulating filters. These +are accept, reject and clear. First we will look +generally at filtering. There are a number of things you can filter in the +DXSpider system. They all use the same general mechanism.
-
Allowing telnet connections is quite simple. Firstly you need to add a line in /etc/services to allow connections to a -port number, like this .... +
In general terms you can create a 'reject' or an 'accept' filter which can have +up to 10 lines in it. You do this using, for example ...
-spdlogin 8000/tcp # spider anonymous login port
+
+accept/spots .....
+reject/spots .....
Then add a line in /etc/inetd.conf like this .... +
where ..... are the specific commands for that type of filter. There are filters +for spots, wwv, announce, wcy and (for sysops) connects. See each different +accept or reject command reference for more details. +
There is also a command to clear out one or more lines in a filter. They are ...
-spdlogin stream tcp nowait root /usr/sbin/tcpd /spider/src/client login telnet
+clear/spots 1
+clear/spots all
There is clear/xxxx command for each type of filter.
-
This needs to be added above the standard services such as ftp, telnet etc. Once this is done, you need to restart inetd -like this .... +
and you can check that your filters have worked by the command ...
-killall -HUP inetd
+
+show/filter
+
For now we are going to use spots for the examples, but you can apply the same +principles to all types of filter.
-
Now login as sysop and cd spider/perl. You can test that spider is accepting telnet logins by issuing the -following command .... -
-
-
-client.pl login telnet
-
-You should get a login prompt and on issuing a callsign, you will be given access to the cluster. Note, you will not -get a password login. There seems no good reason for a password prompt to be given so it is not asked for. -
-
Assuming all is well, then try a telnet from your linux console .... -
-
-
-telnet localhost 8000
-
--
You should now get the login prompt and be able to login as before. -
-
In order to allow cluster node connections, spider needs to know that the connecting callsign is a cluster node. This -is the case whether the connect is incoming or outgoing. -In spider this is a simple task and can be done in runtime. +
There are two main types of filter, accept or reject. You +can use either to achieve the result you want dependent on your own preference +and which is more simple to do. It is pointless writing 8 lines of reject +filters when 1 accept filter would do the same thing! Each filter has 10 +lines (of any length) which are tried in order. If a line matches then the +action you have specified is taken (ie reject means ignore it and accept +means take it)
-
Start up the cluster as you did before and login as the sysop with client.pl. -The cluster node I am wanting to make a connection to is GB7BAA but you would obviously use whatever callsign you -required. -At the prompt type ... +
If you specify reject filters, then any lines that arrive that match the filter +will be dumped but all else will be accepted. If you use an accept filter, +then ONLY the lines in the filter will be accepted and all else will be dumped. +For example if you have a single line accept filter ...
-set/node gb7baa
+accept/spots on vhf and (by_zone 14,15,16 or call_zone 14,15,16)
then you will ONLY get VHF spots from or to CQ zones +14, 15 and 16.
-
The case does not matter as long as you have a version of DXSpider later than 1.33. Earlier versions required the -callsign to be in upper case. -
-
That is now set, it is as simple as that. To prove it, login on yet another console as sysop and issue the command ... +
If you set a reject filter like this ...
-client.pl gb7baa (using the callsign you set as a node)
+reject/spots on hf/cw
-
You should get an initialisation string from DXSpider like this ... +
Then you will get everything EXCEPT HF CW spots. You could make this +single filter even more flexible. For example, if you are interested in IOTA +and will work it even on CW even though normally you are not interested in +CW, then you could say ...
-client.pl gb7baa
-PC38^GB7MBC^~
+reject/spots on hf/cw and not info iota
If the callsign you just set up as a cluster node is for an incoming connect, this is all that needs to be done. -If the connection is to be outgoing then a connection script needs to be written. -
-
Because DXSpider operates under Linux, connections can be made using just about any protocol; AX25, NETRom, tcp/ip, -ROSE etc are all possible examples. Connect scripts live in the /spider/connect directory and are simple ascii files. -Writing a script for connections is therefore relatively simple. -
-
The connect scripts consist of lines which start with the following keywords or symbols:- -
-
-
- -# All lines starting with a # are ignored, as are completely blank lines. - -timeout timeout followed by a number is the number of seconds to wait for a - command to complete. If there is no timeout specified in the script - then the default is 60 seconds. - -abort abort is a regular expression containing one or more strings to look - for to abort a connection. This is a perl regular expression and is - executed ignoring case. - -connect connect followed by ax25 or telnet and some type dependent - information. In the case of a telnet connection, there can be up to - two parameters. - The first is the ip address or hostname of the computer you wish to - connect to and the second is the port number you want to use (this - can be left out if it is a normal telnet session). - In the case of an ax25 session then this would normally be a call to - ax25_call or netrom_call as in the example above. It is your - responsibility to get your node and other ax25 parameters to work - before going down this route! - -' ' is the delimiting character for a word or phrase of an expect/send - line in a chat type script. The words/phrases normally come in pairs, - either can be empty. Each line reads input from the connection until - it sees the string (or perl regular expression) contained in the - left hand string. If the left hand string is empty then it doesn't - read or wait for anything. The comparison is done ignoring case. - When the left hand string has found what it is looking for (if it is) - then the right hand string is sent to the connection. - This process is repeated for every line of chat script. - -client client starts the connection, put the arguments you would want here - if you were starting the client program manually. You only need this - if the script has a different name to the callsign you are trying to - connect to (i.e. you have a script called other which actually - connects to GB7DJK-1 [instead of a script called gb7djk-1]). --
-
There are many possible ways to configure the script but here are two examples, one for a NETRom/AX25 connect and -one for tcp/ip. +
But in that case you might only be interested in iota and say:-
-timeout 60
-abort (Busy|Sorry|Fail)
-# don't forget to chmod 4775 netrom_call!
-connect ax25 /usr/sbin/netrom_call bbs gb7djk g1tlh
-'Connect' ''
-'Connect' 'c np7'
-'Connect' 'c gb7dxm'
-# you can leave this out if you call the script 'gb7dxm'
-client gb7dxm ax25
+accept/spots not on hf/cw or info iota
which achieves exactly the same thing. You should choose one or the other +until you are comfortable with the way it works. You can mix them if you +wish (actually you can have an accept AND a reject on the same line) but +don't attempt this until you are sure you know what you are doing!
-
+
You can arrange your filter lines into logical units, either for your own +understanding or simply convenience. Here is an example ...
-timeout 15
-connect telnet dirkl.tobit.co.uk
-'login' 'gb7djk'
-'word' 'gb7djk'
-# tell GB7DJK-1 that it is connected to GB7DJK
-# you can leave this out if you call this script 'gb7djk'
-client gb7djk telnet
+reject/spots 1 on hf/cw
+reject/spots 2 on 50000/1400000 not (by_zone 14,15,16 or call_zone 14,15,16)
What this does is to ignore all HF CW spots and also rejects any spots on VHF +which don't either originate or spot someone in Europe.
-
Both these examples assume that everything is set up properly at the other end. You will find other examples in -the /spider/examples directory. +
This is an example where you would use a line number (1 and 2 in this case), if +you leave the digit out, the system assumes '1'. Digits '0'-'9' are available. +This make it easier to see just what filters you have set. It also makes it +more simple to remove individual filters, during a contest for example.
-
You start the connection, from within a sysop enabled cluster login, by typing in the word connect followed -by a script name like this .... +
You will notice in the above example that the second line has brackets. Look +at the line logically. You can see there are 2 separate sections to it. We +are saying reject spots that are VHF or above APART from those in +zones 14, 15 and 16 (either spotted there or originated there). If you did +not have the brackets to separate the 2 sections, then Spider would read it +logically from the front and see a different expression entirely ...
-G0VGS de GB7MBC 13-Dec-1998 2041Z >connect gb7djk-1
-connection to GB7DJK-1 started
-G0VGS de GB7MBC 13-Dec-1998 2043Z >
+(on 50000/1400000 and by_zone 14,15,16) or call_zone 14,15,16
This will start a connection using the script called gb7djk-1. You can follow the connection by watching the -term or console from where you started cluster.pl. You should see something like this ... +
The simple way to remember this is, if you use OR - use brackets. Whilst we are +here CASE is not important. 'And BY_Zone' is just the same as 'and by_zone'. +
As mentioned earlier, setting several filters can be more flexible than +simply setting one complex one. Doing it in this way means that if you want +to alter your filter you can just redefine or remove one or more lines of it or +one line. For example ...
-<- D G1TLH connect gb7djk-1
--> D G1TLH connection to GB7DJK-1 started
--> D G1TLH G1TLH de GB7DJK 13-Dec-1998 2046Z >
-timeout set to 15
-CONNECT sort: telnet command: dirkl.tobit.co.uk
-CHAT "login" -> "gb7djk"
-received "
-Red Hat Linux release 5.1 (Manhattan)
-Kernel 2.0.35 on an i586
-"
-received "login: "
-sent "gb7djk"
-CHAT "word" -> "gb7djk"
-received "gb7djk"
-received "Password: "
-sent "gb7djk"
-Connected to GB7DJK-1, starting normal protocol
-<- O GB7DJK-1 telnet
--> B GB7DJK-1 0
-GB7DJK-1 channel func state 0 -> init
-<- D GB7DJK-1
-<- D GB7DJK-1 Last login: Sun Dec 13 17:59:56 from dirk1
-<- D GB7DJK-1 PC38^GB7DJK-1^~
-<- D GB7DJK-1 PC18^ 1 nodes, 0 local / 1 total users Max users 0 Uptime 0 00:00^5447^~
- etc
+reject/spots 1 on hf/ssb
-
With later versions of Spider there is a set/login command for users. This tells them when a user or node logs in -or out. If you do not add a line to your scripts after the final line (or before the client line which should always -be last if needed) then the login/logout information will be sent to users before the login actually -completes. This means if a node is unreachable, it will continue sending logins and logouts to users even though it -is not actually connecting. To avoid this use the following line ... +
would redefine our earlier example, or
-'connect' ''
+clear/spots 1
-
In a script, this might look like ... +
To remove all the filter lines in the spot filter ...
-timeout 35
-abort (Busy|Sorry|Fail)
-connect telnet mary 3000
-'ogin:' 'gb7mbc'
-'>' 'telnet 44.131.93.96 7305'
-'connect' ''
+clear/spots all
-
Cluster links in particular suffer greatly from the presence of telnet echo. This is caused -by the telnet negotiation itself and can create at worst severe loops. At best it creates -unnecessary bandwidth and large logfiles! There are things that can be done to limit this -problem but will not always work dependent on the route taken to connect. -
-
Telnet echo itself should only be a problem if the connection is being made to the telnet -port (23). This port uses special rules that include echo negotiation. If the connection -is to a different port, such as 8000, this negotiation does not happen and therefore no -echo should be present. -
-
Sometimes it is not possible to make a direct connection to another node and this can -cause problems. There is a way of trying to suppress the telnet echo but this will not -always work, unfortunately it is difficult to be more specific. Here is an example -of what I mean ... -
-
-
-timeout 35
-abort (Busy|Sorry|Fail)
-connect telnet mary.lancs.ac.uk
-'ogin:' 'gb7mbc'
-'word:' 'mypasswd'
-'\$' 'stty -echo raw'
-'\$' 'telnet 44.131.93.96'
-'connect' ''
-
-So, the first connection is made by Spider. This is fine as Spider uses the Net_Telnet -script from within perl. This actually uses TCP rather than TELNET so no negotiation -will be done on the first connection. Once connected to mary.lancs.ac.uk, the command -is sent to suppress echo. Now a telnet is made to a cluster node that is accepting -connections on port 23. The problem with this link is that the negotiation is made by -the remote machine, therefore you have no control over it. The chances are that this -link will create echo and there will be no way you can stop it. +
You can filter in several different ways. The options are listed in the +various helpfiles for accept, reject and filter.
-
-
Ok, you should now have DXSpider running nicely and allowing connects by cluster nodes or users. However, it has -to be shutdown and restarted manually and if connection scripts fail they have to be started again manually too, not -much use if you are not at the console! So, in this section we will automate both. Firstly starting the cluster. -
-
This is not only a way to start the cluster automatically, it also works as a watchdog, checking the sanity of -DXSpider and respawning it should it crash for any reason. -Before doing the following, shutdown the cluster as you did earlier. -
-
Login as root and bring up the /etc/inittab file in your favourite editor. Add the following lines to the file near -the end ... +
Sometimes all that is needed is a general rule for node connects. This can +be done with a node_default filter. This rule will always be followed, even +if the link is isolated, unless another filter is set specifically. Default +rules can be set for nodes and users. They can be set for spots, announces, +WWV and WCY. They can also be used for hops. An example might look like +this ...
-##Start DXSpider on bootup and respawn it should it crash
-DX:3:respawn:/bin/su -c "/usr/bin/perl -w /spider/perl/cluster.pl" sysop >/dev/tty7
+accept/spot node_default by_zone 14,15,16,20,33
+set/hops node_default spot 50
This filter is for spots only, you could set others for announce, WWV and WCY. +This filter would work for ALL nodes unless a specific filter is written to +override it for a particular node. You can also set a user_default should +you require. It is important to note that default filters should be +considered to be "connected". By this I mean that should you override the +default filter for spots, you need to add a rule for the hops for spots also.
-
This will automatically start DXSpider on tty7 (ALT-F7) on bootup and restart it should it crash for any reason. -
-
As root type the command telinit q. DXSpider should start up immediately. You will see the output on tty7 -and if you login as sysop you should find everything running nicely. -
-
So far so good, now to automate script connections... -
-
Login as sysop and create a file in /spider/local_cmd called crontab. Edit it with your favourite editor and -add a line like this (I have included a comment) +
Once you are happy with the results you get, you may like to experiment. +
+
The previous example that filters hf/cw spots and accepts vhf/uhf spots from EU +can be written with a mixed filter, for example ...
-# check every 10 minutes to see if gb7xxx is connected and if not
-# start a connect job going
-
-0,10,20,30,40,50 * * * * start_connect('gb7xxx') if !connected('gb7xxx')
+rej/spot on hf/cw
+acc/spot on 0/30000
+acc/spot 2 on 50000/1400000 and (by_zone 14,15,16 or call_zone 14,15,16)
Note that the first filter has not been specified with a number. This will +automatically be assumed to be number 1. In this case, we have said reject all +HF spots in the CW section of the bands but accept all others at HF. Also +accept anything in VHF and above spotted in or by operators in the zones +14, 15 and 16. Each filter slot actually has a 'reject' slot and +an 'accept' slot. The reject slot is executed BEFORE the accept slot.
-
The callsign involved will be the callsign of the cluster node you are going to connect to. This will now check -every 10 minutes to see if gb7xxx is connected, if it is then nothing will be done. If it is not, then a connect -attempt will be started. +
It was mentioned earlier that after a reject test that doesn't match, the default +for following tests is 'accept', the reverse is true for 'accept'. In the example +what happens is that the reject is executed first, any non hf/cw spot is passed +to the accept line, which lets through everything else on HF. The next filter line +lets through just VHF/UHF spots from EU.
-
There are probably lots of other things you could use this crontab file for. If you want to know more about it, look -at the -DXSpider website at the cron page where it is -explained more fully.