Sponsored Content
Operating Systems Solaris Carrier Detection in Solaris 8 for Dial in and Null Modem Connections Post 302820883 by rstor on Thursday 13th of June 2013 03:09:33 PM
Old 06-13-2013
Carrier Detection in Solaris 8 for Dial in and Null Modem Connections

I am having troubles with carrier detection for dialing in via a modem or direct connection via a null modem connection under Solaris 8 (i.e. login session remains active after the modem disconnects). I tried two different dumb modems (which do not respond to AT commands) on the machine that I am dialling into . I tested the CD output on one of the modems and found the appropriate voltage on the CD line when a carrier is detected/not detected (I have confirmed this using a volt meter and applying the appropriate carrier tone via a function generator). If you dial in, login, then hang up, and call back the previous session continues without prompting to login.

I then decided to try a null modem connection. When accessing the serial console on the Solaris 8 system using a null modem cable, the login session remains active when disconnecting the cable and plugging it back in. To my understanding this should not happen, in the first case with the modem, or with the null modem cable as I disabled software carrier detection:

Code:
eeprom ttya-ignore-cd=true  
eeprom ttya-rts-dtr-off=true

Also I've specified the -S n parameter to disable software carrier detection:

Code:
/usr/sbin/pmadm -a -p zsmon -s ttya -i root \
-v `/usr/sbin/ttyadm -V` -fu -m "`/usr/sbin/ttyadm \
-p "login:" -d /dev/term/a -s /usr/bin/login -l contty2H from  -b \
-S n -m ldterm,ttcompat`" -y "dial in/out on serial port"


The instructions that I followed to setup the dial in connection was from Celeste Stokely’s Tutorial on Solaris 2.x Modems and Terminals.

I decided to test out carrier detection on FreeBSD 9.1 on a different machine running within virtual box. I used a usb-serial dongle which shows up as ttyu0 on the BSD machine. Carrier detection appears to work. When I establish a null modem connection (using the same null modem cable that I tried on the Solaris machine) I receive a login prompt. If I login, and then unplug and plug back the null modem cable, I get the login prompt again and the old session does not continue.

I have read a post on-line about carrier detection in Solaris not working and being "broken".

It this correct? Is carrier detection a known bug/issue in Solaris 8?

Last edited by Scott; 06-13-2013 at 06:52 PM.. Reason: Please use code tags
 

9 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

Got connected with Modem but cannot dial Telephone no. to connect to host

Hello There, I configure my Modem as follow. Step1. # admintool & Then from Browse --> Serial Port i select tta port and Edit --> Modify From that i select Template : Modem:Dial Out Baud Rate: 9600 Ok Step 2 # tip /dev/cua/a connected (1 Reply)
Discussion started by: abidmalik
1 Replies

2. UNIX for Dummies Questions & Answers

Hyperterminal null modem connection to Solaris

I am new to Unix. I just got my SUN box from ebay with Solaris supposedly preloaded. The problem is I am unable to connect via Hyperterminal to Solaris, or more to the point, cannot tell if I have a successful connection and that solaris is the one not properly booted up. I hooked up a null... (3 Replies)
Discussion started by: seethams
3 Replies

3. UNIX for Dummies Questions & Answers

Dial-Up Modem

Im using Kinternet with a Lucent modem on Suse 9.0 Ive installed the ltmodem driver and suse says the device is ready and configured. Ive configured it at /dev/ttyS0 This is the log that Kinternet gives after trying to connect: SuSE Meta pppd (smpppd-ifcfg), Version 1.06 on linux. Status... (0 Replies)
Discussion started by: Synbios
0 Replies

4. SCO

Dial-Out & Dial-In Connections in OpenServer 5.0.6.

Friends, I am facing a problem in connecting two SCO Openserver 5.0.6 servers through Dial-Up connectivity as is done in the case of two Windows PCs. Please help me out with the following problems: (a) How to configure the modem? (b) How to setup a Dial-In connection? (c) How to... (1 Reply)
Discussion started by: thecobolguy
1 Replies

5. Solaris

null modem for testing

hi all.. sorry for repeating the same question many times, i just set up a null modem, i am using this as reference : DB25 DB9 -- - 2 TD ---- 2 RD 3 RD ---- 3 TD 4 RTS ---- 8 CTS 5 CTS ---- 7 RTS 7 GND ---- 5 GND 6 DSR -+ +--- 4 DTR 8... (0 Replies)
Discussion started by: waterbear
0 Replies

6. Solaris

help me!!!! how configure modem dial up with smc in solaris 10

Dear All, i have problem during install modem dial up with smc in solaris 10. i can't find "login" because it's stop in _receive started transmit started. thanks for your attention. this is the list during i dial to this number : altconn called Device Type ACU wanted... (0 Replies)
Discussion started by: mr.ridho
0 Replies

7. IP Networking

modem detection

How to get information that where is my modem configured in /dev. I have two modems configured in my device .. one is USB and other is PCI modem.. USB is detected as /dev/USB0. but how to see about PCI modem? (0 Replies)
Discussion started by: s123.radha
0 Replies

8. UNIX for Advanced & Expert Users

Modem (dial up) connecton to Unix machine

Hello to all, I have one problem and hope you'll be able to help me. It's about connecting Windows PC machine to Unix machine via dial up through Hyper terminal. Connection was working in the past. In the meantime, windows machine is replaced (win XP) and unix machine stayed as is. So nothing is... (1 Reply)
Discussion started by: Mick
1 Replies

9. BSD

Carrier Detection in FreeBSD

Regarding carrier detection on FreeBSD 9.1 being run within Virtual Box: I used a usb-serial dongle which shows up as ttyu0 on the BSD machine. Carrier detection appears to work. When I establish a null modem connection I receive a login prompt. If I login, and then unplug and plug back the... (2 Replies)
Discussion started by: rstor
2 Replies
modem(7)						 Miscellaneous Information Manual						  modem(7)

NAME
modem - Describes guidelines for using modems DESCRIPTION
The Tru64 UNIX system enables you to use a variety of modems for point-to-point connections to systems that are not in close proximity to each other. These connections can be Serial Line Internet Protocol (SLIP), Point-to-Point Protocol (PPP), and UNIX-to-UNIX Copy Program (UUCP) connections. In addition, these connections can be basic dial-out/dial-in connections (for example, to log in to a remote system to perform remote system administration). This section presents general guidelines for using modems on Tru64 UNIX systems for all types of connections. See Network Administration for specific information on SLIP, PPP, and UUCP connections. Using the Correct Modem Cables In order to connect a modem to the serial port of your system, you must use the correct cable. If you do not, you might experience signal loss, resulting in the software not functioning properly. The following table lists the cables you should use. The cable connector is either 25-pin or 9-pin, depending on the type of serial port on your system. See the hardware documentation for your system if you are unsure about the type of serial port. Note OPEN DECconnect cables do not provide a sufficient number of wires for full modem control. You should not use them for connecting modems to the system. ------------------------------------------------------------------------------ Cable Number Description ------------------------------------------------------------------------------ BC22E-xx 16-wire modem cable (Male DB25 pin to female DB25 pin cable) BC22F-xx 25-wire modem cable (Male DB25 pin to female DB25 pin cable) BC29P-xx Male DB25 pin to female DB9 pin cable PC modem cable Male DB25 pin to female DB9 pin cable In the previous table, xx denotes the cable length. For example, BC22E-10 is a ten-foot cable. Configuring a System for Dial-In Access After you have obtained the correct cable and connected your modem to it and the telephone network, do the following: Edit the /etc/remote file and create an entry similar to the kdebug entry. For example, if your modem is connected to tty00 and you are going to use a baud rate of 38400 to access the modem, create an entry similar to the following: b38400:dv=/dev/tty00:br#38400:pa=none Note Some modems set their baud rate to the serial port rate. Be sure to access the modem using the same baud rate that you are going to specify to getty or uugetty. Otherwise, you might not be able to log in because of a mismatch in baud rates. See ports(7) if you are unsure which port your modem is connected to. Use the tip command to access the modem as follows: tip b38400 The tip utility responds with a connected message. You can now communicate with the modem. If your modem is using the AT command language, enter the following command: at<Return> If the modem is not in quiet mode, it responds with an OK message. Set the modem up for dial-in access. The following table lists the AT commands required. Most of these command settings are the default settings. -------------------------------------------------------------------------- Command Description -------------------------------------------------------------------------- at&c1 Normal Carrier Detect (CD) operation. Tells the modem to not raise Carrier Detect until it see Carrier Detect from the other modem. at&d2 Normal Data Terminal Ready (DTR) operation. This is important in that it tells the modem to hang up the line when DTR drops. For example, when the user logs off the system. atq1 Sets the modem into quiet mode. Result codes are not sent to the system. ate0 Echo off. This prevents the modem from echoing back the login prompt issued by the getty process. ats0=n Specifies the number of rings to wait before answering. If n = 0 (zero), the modem will not answer. at&w0 Saves the current modem settings in NVRAM. The operating system supports both hardware and software flow control. If the system supports hardware flow control, set the modem and the serial line up to use hardware flow control by using the appropriate commands. If hardware flow control is not supported, you should use software flow control. Edit the /etc/inittab file and create an entry for the modem. If you want to use the modem line in non-shared mode, create an entry similar to the following: modem:23:respawn:/usr/sbin/getty /dev/tty00 M38400 vt100 If you want to use the modem line in shared mode (for dial-out and dial-in connections), use uugetty instead of getty and create an entry similar to the following: modem:23:respawn:/usr/lib/uucp/uugetty -r -t 60 tty00 38400 With uugetty, you will be able to use the tip and cu utilities, but might not be able to use third-party utilities because of dif- ferences in file locking. Note If you want to use the uugetty utility, you must install the UNIX-to-UNIX Copy Facility subset. As root, start the getty or uugetty process by entering the following command: init q The getty or uugetty process starts, then goes to sleep, waiting for someone to dial into the system. Configuring Your System for Dial-Out Access After you have obtained the correct cable and connected your modem to it and the telephone network, do the following: Verify that there is an entry for the modem name specified with the modemtype subcommand in the /etc/acucap file. If your modem does not have an entry in the /etc/acucap file, do the following: Copy an entry similar to that of your modem. The following entry is for a US Robotics modem for use in shared mode with tip: us|US|US Robotics (28.8 fax/data modem): :cr:hu:ls:re:ss=AT ATE1Q0&C0X0&A0 :sr=OK: :sd#250000:di=ATD:dt= : :dd#50000:fd#50:os=CONNECT:ds=d+++dATZ dATS0=2 : :ab=d+++dATZ dATS0=2: Be sure the entry includes at least the AT commands in the following table. The other modem settings can remain as they are. ------------------------------------- Command Description ------------------------------------- ate1 Turns on echoing. atq0 Displays the result codes. Modify the modem attributes to match your modem's attributes and include the debug option (db). With debugging turned on, the modem will provide you with additional information with which to tune the modem attributes in the file. See acucap(4) for more informa- tion. Create an entry in the /etc/remote for the system you want to call. Among the information you can supply is the Tru64 UNIX device, baud rate, and /etc/acucap that defines your modem. The following two entries are for the modem specified in step 1a. tip38400:tc=us38400 us38400|38400 Baud dial out via US Robotics modem: :el=^U^C^R^O^D^S^Q@:ie=#%$:oe=^D: :dv=/dev/tty00:br#38400:ps=none:at=us:du: In the previous example, the first line is an entry that points to the us38400 entry specifying shared capabilities for modems. The second line is the first line of the us38400 entry. The third line defines end-of-line characters, and input and output end-of-file marks. The fourth line defines the UNIX device to open for the connection, the baud rate, the parity, the name of the /etc/acucap file entry, and the dial-up line. See remote(4) for more information. If you use getty to provide access to the system from a modem and a getty process is already running, do the following: Edit the /etc/inittab file and put a comment character (#) at the beginning of the modem entry. Issue the init q command to terminate the getty process. Use the tip command, specifying the -baud_rate flag and the telephone number to dial out as follows: tip -38400 8881234 In this example, tip strips off the minus sign (-) from the baud rate and concatenates the tip command name and the baud rate to create the string tip38400. Then, tip searches the /etc/remote file for the entry matching the string. The entry in the /etc/remotes file, points the capability information in the us38400 entry to initialize the modem. By specifying the telephone number on the command line, you can share the same modem attributes for outgoing connections that have different telephone numbers. When you log off the remote system and exit tip, the modems saved settings are restored, readying the modem for the next user. If used in shared mode, the modem is available for dial-in access. RELATED INFORMATION
Commands: cu(1), tip(1), getty(8), uugetty(8). Files: acucap(4), inittab(4), remote(4). Devices: ports(7). Network Administration delim off modem(7)
All times are GMT -4. The time now is 08:47 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy