Installation and Configuration

The Kernel

These days you should take a kernel version 1.3.97 or younger (there are kernel internal drivers available since kernel 1.3.69, but this thing only is stable enough since 1.3.97).

Now, while kernel 2.0 is released, we will talk about this kernel. Nowadays it is recommended to use kernel version 2.0.27, which cooperates flawlessly with isdn4k-utils-2.0. You should look for the kernel at your SunSite, e.g. at

  ftp.leo.org/pub/comp/os/linux/Linus/v2.0/

  ftp.leo.org/pub/comp/os/linux/Linus/v2.0/modules-2.0.0.tar.gz

  ftp.leo.org/pub/comp/os/linux/sunsite/docs/HOWTO/Kernel-HOWTO.gz

If you want to use isdn4linux to drive an ISDN card you don't need to apply any more a patch to this kernel (only kernel 2.0.0 needed the two patches isdn4kernel-2.0-patch1+2). But: Most passive ISDN cards with Siemens chip set (Teles, Creatix, AVM, Elsa, ...) only work, if you use the driver package "HiSax". If you run such a card you must fetch this driver, too, and put it into/usr/src:

  ftp.franken.de/pub/isdn4linux/HiSax/

  root:# cd /usr/src
  root:# tar zxfv HiSax_1.5.patch_for_2.0.tar.gz
  root:# patch -p <HiSax_1.5.patch_for_2.0
  root:# _

Code maturity level options":
  Prompt for development and/or incomplete code/drivers: No
Section "General Setup":
  Networking support: Yes
Section "Networking options":
  TCP/IP networking: Yes
  all other items are up to you
Section "Network device support":
  Network device support: Yes
  PPP (point-to-point) support: Yes  
  all other items are up to you
Section "ISDN subsystem":
  Only if you need isdn4linux:
  ISDN support: Yes
  Support synchronous PPP: Yes (!)
  Use VJ compression with synchronous PPP: Yes
  Support audio via ISDN: Yes
  Support generic MP (RFC 1717): Yes
  Mark your own PC card here, too.

ISDN Card Driver Software

If you want to drive an ISDN card you also need the current version of Fritz Elfert's "isdn4kernel utilities". If you have an older version of isdn4linux you must update: the command "isdnctrl pppbind" must exist! Find out - type in isdnctrl and have a look at the available options.

  ftp.franken.de/pub/isdn4linux/isdn4k-utils-2.0.tar.gz

  /usr/src/isdn4k-utils-2.0

You also need to define the card parameters - please read the ISDN4Linux manual

  /usr/src/linux/Documentation/isdn/README

Configuration

Configuration files

Eine Reihe weiterer Dateien müssen angelegt werden. So ist für jeden Provider je eine Datei pro Einwahl-Telefonnummer herzustellen, in der alle wichtigen Daten enthalten sind. Die PPP-Dämonen benötigen überdies ein paar weitere Dateien. Das werden wir nun der Reihe nach besprechen.

There are also some more files necessary. So you need one file per provider and per dial-in number. And the PPP daemons need some more files, too. We will discuss this now.

If you did load down this WWW pages as package "leafsite.tar.gz", you find the scripts in the subdirectory "scripts".

Some Pre Work

If you have used the old "isdn" package before, stop the isdn system using

    root:# <startup_path>/i4l stop (or "rc.isdn stop" or whatever)
    root:# _
  

(<startup_path> is the path, where all the system bootup files are located).

Then remove (or save, if you like) some old files:

    root:# rm <startup_path>/i4l (if you use a newer SuSE distribution)
    root:# rm <startup_path>/rc.isdn
    root:# rm /sbin/isdn
    root:# rm /etc/i4l.provider (or /etc/i4l.config, if older "isdn" version)
    root:# rm /etc/i4l.secrets  (or /etc/i4l.param, if older "isdn" version)
    root:# _
  

  root:# mkdir /usr/lib/connect
  root:# mkdir /usr/lib/connect/providers
  root:# mkdir /var/lib/connect
  root:# _

Provider Data

Beispiel für eine isdn4linux-Datei

  #!/bin/bash
  MODE=i4l
  PHONE=0891234567
  IP_ADDRESS=123.234.210.109
  OPTIONS_FILE=/etc/ppp/options.ipppd

  #!/bin/bash
  MODE=modem
  IP_ADDRESS=234.123.134.56
  DEVICE=ttyS1
  OPTIONS_FILE=/etc/ppp/options.pppd
  CHAT_SCRIPT="ABORT BUSY ABORT 'NO CARRIER' '' ATZ0 OK ATD0,08912345 CONNECT"

You can load down a database with date for several universities and other providers.

By the way: I would be pleased to get the configuration file for your provider - just mail it!

Default Values

/usr/lib/connect/base
#!/bin/bash
# (c) 1997 Bernhard Hailer (GNU GPL V.2)

# Edit this file for your needs

# local settings
# ==============

# Fully qualified host name
read MY_HOSTNAME </etc/HOSTNAME                          # read host's name
# MY_HOSTNAME=foo.bar.com

# Host phone number and MSN (EAZ) - replace by your numbers!
MY_PHONE=817890032                                          # no leading zero!
MY_EAZ=90032

# Email address for fetching mail - replace by your address!
MY_EMAIL_ADDRESS=dl4mhk@lrz.uni-muenchen.de


# extra start commands for rc.connect (e.g. module loading)
# ---------------------------------------------------------
function Con_Start()
{
  insmod /lib/modules/`/bin/uname -r`/misc/isdn.o
  insmod /lib/modules/`/bin/uname -r`/misc/hisax.o io=3,2,12,0xd80 HiSax_id=Teles0
  #insmod /lib/modules/`/bin/uname -r`/misc/teles.o io=0,12,0xd80,2 teles_id=Teles0
  #rmmod teles.o
  #insmod /lib/modules/`/bin/uname -r`/misc/teles.o io=0,12,0xd80,2 teles_id=Teles0
  return
}

# extra stop commands for rc.connect (e.g. module unloading)
# ----------------------------------------------------------
function Con_Stop()
{
  rmmod hisax.o  
  #rmmod teles.o
  sleep 1
  rmmod isdn.o
  return
}

# Default remote providers for regular connects
DEFAULT_REMOTES="lrz-d1 lrz-d2"

# default device where your modem is connected - no leading "/dev/"!
DEFAULT_DEVICE="ttyS1"

# Maximum number of dialin attempts
declare -i DEFAULT_MAX_TRIES
DEFAULT_MAX_TRIES=4

# Maximum idle time before hangup (you should use a time of about 300 secs
# here, because it is more expensive to dial often than to hold a line!)
# This only works for isdn4linux connections.
declare -i HUPTIMEOUT
HUPTIMEOUT=300             # 5 min

Here also some default values are defined. DEFAULT_REMOTES contains the file names of the remotes which shall be called by default (if you define more than one, "connect" tries to call one after the other until the connection establishes). DEFAULT_MAX_TRIES says how often this should happen. HUPTIMEOUT is valid only for isdn4linux. Enter here after how many idle time isdn4linux shall hang up (modems: read the manual, please). And DEFAULT_DEVICE is the name of the serial interface the modem normally is connected.

We will discuss now this script rc.connect.

What Happens While Booting

simpleinit

You must create this file. Before this you must add the following to /etc/rc.d/rc.M, because this new file must be known by the booting system:

/etc/rc.d/rc.M, section "# Initialize the NET subsystem."
  . /etc/rc.d/rc.inet1
  . /etc/rc.d/rc.connect    # <-- add this line!
  . /etc/rc.d/rc.inet2

sysvinit

This sequence is a bit "tricky": a "master script" looks into the directory of the run level (./rc1.d, ./rc2.d, ./rc3.d and so on) what to do. Therein are a lot of soft links to the scripts I wrote above. All links are named

  SnnScriptName

  KnnScriptName

  root:# cd /sbin/init.d/rc2.d  # (please verify path!!)
  root:# ln -s ../rc.connect K20rc.connect
  root:# ln -s ../rc.connect S20rc.connect
  root:# _

Remark for S.u.S.E. users (version 4 and newer): A similar file exists here, named i4l, also there may exist a file i4l_hardware. These files must be removed, and also their calling scripts in /sbin/init.d/rc2.d. Of course so the I4L_* entries in the S.u.S.E. configuration file /etc/rc.config are obsolete now.

Sorry for this inconvenience, but this is necessary to get a distribution independent package.

System Start and Stop

/sbin/init.d/rc.connect (cutting)
  /sbin/isdnctrl verbose 0  # For debugging set to 2 (max. 4)
  # ISDN device drivers     ippp0 (PPP)
  /sbin/isdnctrl addif      ippp0
  /sbin/isdnctrl pppbind    ippp0 0
  /sbin/isdnctrl addphone   ippp0 out $PHONE      # dial-out number
  /sbin/isdnctrl addphone   ippp0 in $MY_PHONE    # my telephone no
  /sbin/isdnctrl eaz        ippp0 $MY_EAZ         # my MSN / EAZ
  /sbin/isdnctrl huptimeout ippp0 $HUPTIMEOUT     # defined in $BASE
  /sbin/isdnctrl secure     ippp0 on              # nobody may enter
  /sbin/isdnctrl l2_prot    ippp0 hdlc
  /sbin/isdnctrl l3_prot    ippp0 trans
  /sbin/isdnctrl encap      ippp0 syncppp
  /sbin/ifconfig ippp0 $MY_HOSTNAME pointopoint $IP_ADDRESS metric 1
  /sbin/route add default ippp0                   # interface definitions 
  /sbin/ipppd /dev/ippp0 file $OPTIONS_FILE &
  /sbin/route del default
  ifconfig ippp0 down

You must make this file executable by typing in chmod 744 now.

You see: some of the environment variables defined above are used here! Some commands are remarkable: the "pppbind" command is against side effects, if more than one ipppd is started. If you don't call this command, all ipppd's use the passwords defined for the first one! The last two commands are also essential: only if no ipppd is up you can start a regular pppd for modems without problems!

By the way: We don't call the standard PPP daemon pppd 2.2.0[ef] here, but an especially patched version named "ipppd". This pppd is part of the ISDN4Linux package and is set while installation to /sbin. Anyway the PPP HOWTO and the pppd manpage is valid.

More Files

/etc/ppp/options
# comment out the following three lines if you don't need 
# dynamic IP negotiation.
ipcp-accept-local
ipcp-accept-remote
noipdefault
# more pppd/ipppd options
lock
mru 1500
mtu 1500
debug
-detach

• the ipppd needs other options than the pppd,
• the options vary from provider to provider.

sample file for the pppd
   pppd
# /etc/ppp/options
crtscts
user hailer

sample file for the ipppd
# /etc/ppp/options for ipppd
useifip
-vjccomp
-ac
-pc
-detach
-bsdcomp
-vj
user hailer

/etc/resolv.conf: (see provider database)
search <what_you_need>
nameserver <IP 1st nameserver> 
nameserver <IP 2nd nameserver> 
nameserver <IP 3rd nameserver>

/etc/host.conf:
  order hosts bind
  multi on

/etc/hosts:
  # For loopbacking.
  127.0.0.1       localhost
  # My own IP address
  192.168.1.1     machine.name                alias    # or your own IP address
  # (192.168.x.x is free, you always may use it!)
  # example entries
  129.187.10.22   sun3.lrz-muenchen.de        sun3     # (example remote)
  129.187.13.48   sunmailhost.lrz-muenchen.de getmail  # (example, for email)
  129.187.13.48   news.lrz-muenchen.de        getnews  # (example, for news)

Authentification

  root:# chmod 600 /etc/ppp/pap-secrets (or /etc/ppp/chap-secrets)
  root:# _

PAP

/etc/ppp/pap-secrets
  # Secrets for authentification using PAP
  # client          server           secret          IP addresses
  <provider_login>  <1st provider>   '<password>'    -
  <provider_login>  <2nd provider>   '<password>'    -

• It is recommended to nest the password in apostrophes. So no error appears if a "#" is in the password. (Thanks to Michael Matschilles <mat@pascal.bmw.de> for the hint!)
• In many cases it is easier to enter an asterisk "*" instead of the provider's name in the server column.

Don't forget to secure it with chmod 600 /etc/ppp/pap-secrets!

CHAP

/etc/ppp/chap-secrets
  # Secrets for authentification using CHAP
  # client          server             secret       IP addresses
  <provider_login>  <1st provider>      <password>
  <1st provider>     <provider_login>   ""
  <provider_login>  <2nd provider>      <password>
  <2nd provider>     <provider_login>   ""

Some Polish

  daemon.*                      /var/log/ppp-log

Running

The newer kernels since 1.3.100 have a something painful behavior: they set the default route automatically when a interface is defined. To prevent collisions you need to wait until a connect is completely built up (dialing, PPP handshake) before setting the default route. The following script does this. It is written so that you may call it more than once, so the first application (e.g. exchanging email) makes the connect, and the next applications don't need to open more lines. The last application cleans up: it hangs up and deletes the default route. Call this script as /sbin/connect on und /sbin/connect off. Here's only a very short example; you can load down a very sophisticated script by clicking onto the headline.

Put the script to /sbin and make it executable (route may be called only by "root"!):

  root:# chmod 744 /sbin/connect
  root:# _

/sbin/connect
  #! /bin/bash

  PATH=/sbin:/usr/sbin:/bin:/usr/bin

  #  ISDN4Linux:

  case $1 in
    on)
      isdnctrl dial ippp0       #  connect
      sleep 5                   #  wait until open
      route add default ippp0   #  set route
      ;;
    off)
      isdnctrl hangup ippp0     #  disconnect
      route del default         #  and delete route
      ;;
    *)
      echo -e "\a Usage: 'isdn on' or 'isdn off'"
      ;;
  esac

  # Modem:

  IF_FILE=/var/lib/connect/interface
  case $1 in
    on)
      pppd connect "chat $CHAT_SCRIPT" file $OPTIONS_FILE /dev/$DEVICE &
      # the interface name was saved now by /etc/ppp/ip-up in IF_FILE.
      sleep 1
      echo "Sleeping 40 seconds for establishing connection..."
      sleep 40
      read INTERFACE <$IF_FILE
      route add default $INTERFACE
      ;;
    off)
      kill -HUP `cat /var/lock/LCK..$DEVICE`
      route del default
      ;;
  esac

For modem usage INTERFACE must be retrieved with a trick: while startup of pppd the script /etc/ppp/ip-up is called with these arguments:

  ip-up interface device speed local_address remote_address

/etc/ppp/ip-up
#!/bin/bash
# This script is called by (i)pppd while starting up.
# It is called this way:
#   ip-up interface device speed local_address remote_address.
#   So you can get the used interface by fetching $1
echo $1 >/tmp/connect_interface.tmp

Hints for more experiments:

• The "isdnctrl dial ippp0" makes the connection - from there on it costs your money. We prevent connection failures this way because the system can hang after the connect took place (may be an error in ipppd). These hangs may appear if the system must dial after the connect command (telnet etc.).
• It is also important that you set the default route after completion of the connect. Otherways the kernel kills the route too early and sends messages like "network not reachable", if you want to connect to another computer.

Test:

  root:# connect
  Calling ippp0
  Dialing of ippp0 triggered
  Sleeping 8 sec for PPP handshaking...
  Line open - checking...
  :-) Line is ok - have fun!
  root:# telnet sun3
  [...]

  root:# connect off
  Last application stopped - closing line.
  prov0 hung up
  prov1 already closed! To force closing use "connect off all"
  root:# _

What can "connect" do?

"connect" (or "connect on")        connect default remote
"connect off"                      disconnect

"connect off all"                  disconnects all channels

"connect remote1 (on)"             connect to remote1
"connect remote1 off"              and disconnect from it

"connect remote1 remote2 remote3 ..."

"connect remote1 route Netz-IP"    connect via route
"connect remote2 route default"    connect via defaultroute

If the dial-in ports of your provider are heavily loaded, you may want to have a maximum number of dial attempts:

"connect remote1 maxtries number"       

And this is similar:

"connect remote1 device ttySn"       

More Utilities

Have a look at the README by Fritz Elfert.