I have not tested this, but it should be rather simple.
Note: rh-isdn-conf does not support multiple configurations right now (propably never will), so you have to make these changes always manually.
First of all you have to either copy /etc/ppp/ippp0.d to eg. /etc/ppp/ipppX.d, X being one of the devices /dev/ippp[0-9]*.
Make sure to add a new entry in pap-secrets and
have the matching user-entry in options.
You have to copy /etc/sysconfig/network-scripts/ifcfg-ippp0 as well and adjust it to your needs.
You will propably better set ONBOOT to "no" and bring devices up and down by e.g. a cron-script.
In your cron-script do not forget to modify your resolv.conf. Alternatively take a look at DNRD.
Note: If you have a caching-only nameserver you have to alter named.conf or named.boot instead. You have to change the forwarder according to your IPS's name-server.
Take a look at ippp0.conf and ippp1.conf, the first one is a sample for a master-device-, the second for a slave-device-configuration. Take a look at Section 4.3 to get the meaning of the settings.
Include your new ISP's number in callerid.conf.
Well, if all your cards use the hisax-driver it is rather simple: Just enter the parameters like IO, MEM etc. for all your cards seperated by a single comma in /etc/sysconfig/isdn like e.g.:
I4L_IO="0x0360,0x0400" I4L_ID="Elsa%Teles" |
1999/12/29, http://www.webideal.de/rh-isdn/