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### 7. Questions and answers

### 7.1 Frequently Asked Questions

#### I can't get kppp to work. kppp tells me that pppd has died or that a timeout has expired!

Did you read the this manual carefully? Here are once more the most common pitfalls.

- Click on the "Details" button. kppp will you give an excerpt from the PPP log messages (may not work on non-Linux systems, or even on some Linux distributions). The log will help you to track down the bug.
- Make sure that pppd is the actual pppd binary not a script
- Make sure that pppd is setuid root. You may set this mode by issuing chmod u+s pppd as root.
- Make sure that your `/etc/ppp/options` file exists and that it doesnīt contain any conflicting entries. If in doubt: Leave this file empty.
- Using the symbolic link `/dev/modem` may cause some conflicts. Eliminate this source of trouble by using the real device, i.e. `/dev/cuaX` or `/dev/ttySX`. NOTE: COM1 equals ttyS0, COM2 is ttyS1 and so on.
- Make sure you set the right permission. In case of trouble you might want to run it as root first and then later, when everything is working o.k give it less harmful permission if you can not afford to run kppp setuid root. The proper way to proceed would probably be creating a "modem" group.
- You might be launching pppd too early, i.e. before the remote server is ready to negotiate a PPP connection. If you are using a login script, you should use the built-in terminal to verify your login procedure. Some providers will require you to issue a simple "Send" or "Send ppp" to launch PPP. Some users even reported, that they had to append "Pause 1" or "Pause 2" to their script to solve timing conflicts.

If nothing helps, you might obtain some debugging info from your systems log by issuing:

> `

>     # tail /var/log/messages

> `

#### kppp tells me ``Sorry, can't open the modem''.

This means that kppp doesn't have permissions to open the modem device or that you selected a modem device on the Modem Tab Dialog that is not valid. First make sure you selected the right modem device. Once you are sure you have selected the right modem device, you must give kppp the right permission to access the modem device and to be able to modify `/etc/resolv.conf` in case you want kppp to configure DNS correctly for you. If you can afford to run kppp setuid root this would solve all access problems for you, if not you will have to figure out what the right permissions are for your purposes. In order to give kppp setuid root permissions do the following:

> `

>     % su root
>     # chown root:root ${KDEDIR}/bin/kppp
>     # chmod +s ${KDEDIR}/bin/kppp
>     # exit

> `

#### kppp tells me it can't create a modem lock file.

This in most instances means that you have installed kppp without SETUID bit on while you, the person executing kppp, doesn't have write access to the lock file directory which by default is `/var/lock`. This for example is the case on Red Hat systems. Check the modem dialog for the precise location you have chosen. The solution is easy -- either run kppp SETUID if you can afford to, or give regular users write access to `/var/lock` or create a modem group that will have access to the `/var/lock` file.

#### Why is kppp installed with the SETUID bit on?

There is no need for the SETUID bit, if you know a bit of Unix systems administration. Simply create a modem group, add all users that you want to give access to the modem to that group and make the modem device read/writable for that group. Also if you want DNS configuration to work with kppp, then `/etc/resolv.conf` must be read/writable by the members of that group. The same counts for `/etc/ppp/pap-secrets` and `/etc/ppp/chap-secrets` if you want to use the built-in PAP or CHAP support, respectively.

Please do not criticise me for installing kppp with setuid bit on, I simply can no longer handle the amount of mail I used to get from desperate users who had problems getting kppp to work because they didn't understand enough about Unix and device permissions.

The kppp team has lately done a lot of work to make kppp setuid-safe. But it's up to you to decide if you install and how you install it.

You might also want to read the Security section.

#### kppp just sits there and waits: Expecting OK

- Have you played with the CR/LF setting? Try CR, LF or CR/LF.
- Your modem might need some time to respond to its initialisation. Open the "Modem Commands" dialog on the "Modem" tab and adjust the "Pre-Init" and "Post-Init" delays. See if you are successful when drastically increasing their values and do some fine tuning later.

#### The connection works fine but I canīt start any applications.

You probably have activated the Auto-configure hostname option and the X Server has problems connecting to your newly named host. If you really need this option (chances are that you donīt) you are on your own to setup the appropriate authorisations. Issuing xhost + before starting the connection would do the job, but be warned of any security risks that involves since everyone else is granted access to your X Server.

Another source of trouble (note to Red Hat users): one of the pre-installed network scripts might be playing tricks on you. Rename `/etc/ppp/ip-up` to stop pppd from executing it automatically on every connection.

#### kppp reports a successful connection, but Netscape just says "The server does not have a DNS entry"

Try pinging another server by its IP number, e.g. `ping 195.0.254.76`. If that works you should

- check if you provided kppp with at least one DNS address
- check the contents of `/etc/host.conf`. There should be a line saying something similar to `order hosts, bind`. The `bind` keyword advises the resolver library to include a name server query when performing an address lookup.

#### How do I make kppp send a \n or a \r?

Just send an empty string such as in the following script:

> `

>     Send                                   # send an empty string
>     Expect      ID:
>     Send        itsme
>     Expect      word:
>     Send        forgot
>     Expect      granted
>     Send        ppp

> `

#### kppp complains: "Can't create lock file"

This means that you don't have permissions to create a lock file. If you chose to use a lock file you must have write permissions to the directory (typically /var/lock). This is of course no problem if you have given kppp setuid permissions. Please read the section on lock files .

#### My modem makes much noise when dialling!

Click on "Setup", "Modem". You can control the modem volume here in three steps: off, medium and high. For most modems "medium" and "high" result in the same volume. If that doesn't work, make sure that the correct settings for your modem are specified in "Setup"/"Modem"/"Modem commands"!

#### I turned the modem volume "off" and verified the modem commands,but I still hear that noise when dialling!

The volume initialisation string can get lost if your modem can't cope with the speed it revives its command from kppp. Increase the value of "Post-Init Delay" in "Setup"/"Modem"/"Modem commands"!

Click on "Setup", "Modem". You can control the modem volume here in three steps: off, medium and high. For most modems "medium" and "high" result in the same volume. If that doesn't work, make sure that the correct settings for your modem are specified in "Setup"/"Modem"/"Modem commands"!

#### kppp reports an unusual modem speed like 115200, 57600 or similar

Many modems only report the speed of the serial line and not the speed over the telephone line as default. You must configure these modems to report the true line speed (add to modem init or dial string). For many modems this command is "ATW2". If you want to add it to the dial-string (typical "ATD"), the new dial string would be "ATW2D".

#### kppp reports "Unknown speed"

New modems often have very complex connection messages like "CONNECT LAP.M/V42.bis/115000:RX/31200:TX", and kppp cannot parse this message correctly. Turn on "Show Log" and you'll see the connection speed. I'm currently working on a solution for this, and the parser is now much better, but still not perfect.

#### Slow connection speed

If you are not satisfied with the modem speed, make sure you've set the connection speed ("Setup" / "Device" / "Speed") to 57600 or higher. Make sure that your serial ports support higher speeds. Many systems based on i486 do not work correctly when you set the speed to 115200. If you have a 8250 UART chip, it won't work. If you have a 16550 or 16550A it should work flawlessly.

Additionally, consult your modem manual to look for init strings that enable a high speed mode.

#### REALLY slow connection speed

If data drips in at a rate of just a few bytes per second you should check your hardware setup. If moving your mouse speeds up the transmission this is definitely a hardware issue.

Obtain some information about your serial port with `setserial -a /dev/ttySx` and check for interrupt conflicts with other components of your system.

#### My phone line needs pulse dialling instead of tone dialling (or vice-versa)

You must modify you modem dial string. Nearly all modems support the following AT-commands:

- ATDT - selects tone dial
- ATDP - selects pulse dial

#### kppp makes really strange things (whatever)

Did you compile it or the libraries with gcc-2.8? This version of gcc is somewhat broken, and it will not work as expected.

#### How do I write a telephone cost rules file?

Just follow the TEMPLATE rules files supplied with kppp. You should be able to find a copy in the `${KDEDIR}/share/apps/kppp/Rules`. Use the `-r` kppp command line options to check the syntax of your proposed rules file.

#### I have written a telephone cost rules file for my region. Where can I submit it so that others can make use of it?

I would love to receive any rule files written. I will make them available on my kppp web page. Before you send me a new rules file make sure it is not already available on the kppp web page. Then email the new rules file one of the current maintainers.

#### Can my phone cost rulefile contain fractional time units, e.g. "(0.17,45.5)"?

Yes this is possible. But you should not use unusual small time units (below tenth of a second), because this would result in higher CPU load (though I doubt you'll notice with a modern CPU :-)

#### My country observes a moving holiday different from easter.

In that case you need to write new code that allows for the computation of that holiday. Please have a look at ruleset.cpp and emulate the ``easter'' example. Then send us the patches.

#### kppp tells me "Sorry, the modem is not ready".

Uncheck the "Modem Asserts CD Line" option you will find on the Modem tab. Your hardware seems to be missing support for sensing the "Carrier Detect" line.

#### The connection fails with "Timeout expired while waiting for the PPP interface to come up!"

The PPP daemon didn't get into contact with the remote server in time. Listed below are a few hints that helped several users:

- Play with the setting of Line Termination (Device tab)
- Add a "Pause 1" or "Pause 2" scripting command (even if you're using PAP or CHAP)
- Increase the pppd timeout (PPP tab)
- Use the real device instead of a symbolic /dev/modem link
- Toggle the "Use Lock File" setting (Device tab)

#### "Sorry, the modem is busy"

- you might be an unlucky owner of a WinModem
- did you correctly configure the serial port or internal modem ? The interrupts might not be set up correctly.
- verify that no other software is currently accessing the modem
- If you're using a 2.2.5 (or newer) Linux kernel there might be a conflict with the serial support module. See http://www.suse.de/sdb/en/html/sf_seriell.html for further details.

#### How do I disable dial tone detection ?

Put X3 into your dial string, e.g. ATX3DT.

## 7.2 How to interpret the system's log

#### Serial line is looped back

Short answer: You haven't started the PPP software on the peer system.

See a posting from Al Longyear on http://www.dejanews.com/getdoc.xp?AN=184945314 for a more detailed explanation.

#### Signal 15

If you see the following lines you've probably just received a timeout error from kppp, too. kppp has been waiting for the PPP interface to come up and gave up after the specified timeout. pppd was signaled to shut down with signal number 15, i.e. SIGTERM.

> `

>     pppd[26921]: pppd 2.3.5 started by me, uid 500
>     pppd[26921]: Using interface ppp0
>     pppd[26921]: Connect: ppp0 <--> /dev/ttyS0
>     pppd[26921]: Terminating on signal 15.
>     pppd[26921]: Connection terminated.
>     pppd[26921]: Exit.

> `

#### Receive serial link is not 8-bit clean

The PPP daemon is alarmed by the fact that all data it receives has bit 8 set to zero. In most cases this simply indicates that the remote PPP server isn't running yet. You might be still confronted with a login prompt that echoes back all data sent by your pppd.

#### can't locate module ppp-compress

Do you get the following messages ?

> `

>     modprobe: can't locate module ppp-compress-21
>     modprobe: can't locate module ppp-compress-26
>     modprobe: can't locate module ppp-compress-24

> `

Just add the lines

> `

>     alias ppp-compress-21 bsd_comp
>     alias ppp-compress-24 ppp_deflate
>     alias ppp-compress-26 ppp_deflate

> `

to your /etc/conf.modules file.

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