Technical data

A. Appendix to basepackage
As a cable to the terminal or PC with terminal emulation a Null Modem Cable (Page 340)
is used. Using a standard null modem cable is discouraged because these have bridges on the
handshake wires. If Terminal or PC are powered off (or no terminal emulation is loaded) the
use of a standard null modem cable can thus lead to a hangup.
This is why a special wiring is needed here for using fli4l also when the terminal is deactivated.
You need a 3-wire cable, with some bridges on the plug. See Nullmodemkabel (Page 340).
A.3. Programs
To save space on the boot media the program “BusyBox” is used. Ti is a single executable
containing the standard Unix programs
[, [[, arping, ash, base64, basename, bbconfig, blkid, bunzip2, bzcat, bzip2,
cat, chgrp, chmod, chown, chroot, cmp, cp, cttyhack, cut, date, dd, df,
dirname, dmesg, dnsdomainname, echo, egrep, expr, false, fdflush, fdisk, find,
findfs, grep, gunzip, gzip, halt, hdparm, head, hostname, inetd, init, insmod,
ip, ipaddr, iplink, iproute, iprule, iptunnel, kill, killall, klogd, less, ln,
loadkmap, logger, ls, lsmod, lzcat, makedevs, md5sum, mdev, mkdir, mknod,
mkswap, modprobe, mount, mv, nameif, nice, nslookup, ping, ping6, poweroff,
ps, pscan, pwd, reboot, reset, rm, rmmod, sed, seq, sh, sleep, sort, swapoff,
swapon, sync, sysctl, syslogd, tail, tar, test, top, tr, true, tty, umount,
uname, unlzma, unxz, unzip, uptime, usleep, vi, watch, xargs, xzcat, zcat
. These are mostly “minimalistic” implementations which do not cover the full functional range
but fully reflect the modest requirements of fli4l.
BusyBox is GPL’ed and its source can be obtained at
http://www.busybox.net/
A.4. Other i4l-Tools
There are other tools for isdn4linux that could be used for fli4l. It could be that isdnlog is
more adequate as a tool to compute online-fees but it’s size is 10 times higher than imond’s
which additionally does monitoring, controlling and Least-Cost-Routing.
A.5. Debugging
Console-Outputs are most helpful for hunting bugs. But these go by so fast on the screen,
don’t they? Hint: SHIFT-PAGE-UP scrolls back, SHIFT-PAGE-DOWN scroll forwards.
If the error message “try-to-free-pages” occurs during router use there is not enough RAM
left for the programs. Try the following options to recover:
• add more RAM
• use less Opt-Packages
• try a harddisk-installation according to Typ B (Page 15)
proc-files can help debugging, for example executing
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