This chapter explains how to start up UUCP operations afteryou have modified the database file relevant to your machines. The chapter contains procedures and troubleshooting information for setting up and maintaining UUCP on machines running the Solaris environment.
For incoming UUCP (uucico) requests from remote machines to be handled properly, each machine has to have a login on your system.
Here is a typical entry that you might put into the /etc/passwd file for a remote machine permitted to access your system with a UUCP connection:
Ugobi:*:5:5:gobi:/var/spool/uucppublic:/usr/lib/uucp/uucico |
By convention, the login name of a remote machine is the machine name preceded by the uppercase letter U. Note that the name should not exceed eight characters, so that in some cases you might have to truncate or abbreviate it.
The previous entry shows that a login request by Ugobi is answered by /usr/lib/uucp/uucico. The home directory is /var/spool/uucppublic. The password is obtained from the /etc/shadow file. You must coordinate the password and the login name with the UUCP administrator of the remote machine. The remote administrator must then add an appropriate entry, with login name and unencrypted password, in the remote machine's Systems file.
Similarly, you must coordinate your machine's name and password with the UUCP administrators of all machines that you want to reach through UUCP.
UUCP comes with four shell scripts that poll remote machines, reschedule transmissions, and clean up old log files and unsuccessful transmissions. The scripts are:
uudemon.poll
uudemon.hour
uudemon.admin
uudemon.cleanup
These shell scripts should execute regularly to keep UUCP running smoothly. The crontab file to run the scripts is automatically created in /usr/lib/uucp/uudemon.crontab as part of the Solaris installation process, if you select the full installation. Otherwise, it is created when you install the UUCP package.
You can also run the UUCP shell scripts manually. The following is the prototype uudemon.crontab file that you can tailor for a particular machine:
# #ident "@(#)uudemon.crontab 1.3 93/02/02 SMI" # 48 8,12,16 * * * /usr/libuucp/uudemon.admin 45 23 * * * /usr/lib/uucp/uudemon.cleanup 0 * * * * /usr/lib/uucp/uudemon.poll 11,41 * * * * /usr/lib/uucp/uudemon.hour |
To activate the uudemon.crontab file, become superuser and type:
# su uucp # crontab < /usr/lib/uucp/uudemon.crontab |
The default uudemon.poll shell script reads the /etc/uucp/Poll file once an hour. If any machines in the Poll file are scheduled to be polled, a work file (C.sysnxxxx) is placed in the /var/spool/uucp/nodename directory, where nodename represents the UUCP node name of the machine.
The shell script is scheduled to run once an hour, before uudemon.hour, so that the work files are there when uudemon.hour is called.
The default uudemon.hour shell script:
Calls the uusched program to search the spool directories for work files (C.) that have not been processed and schedules these files for transfer to a remote machine.
Calls the uuxqt daemon to search the spool directories for execute files (X.) that have been transferred to your computer and were not processed at the time they were transferred.
By default, uudemon.hour runs twice an hour. You might want it to run more often if you expect high failure rates of calls to remote machines.
The default uudemon.admin shell script does the following:
Runs the uustat command with p and q options. The q reports on the status of work files (C.), data files (D.), and execute files (X.) that are queued. The p prints process information for networking processes listed in the lock files (/var/spool/locks).
Sends resulting status information to the uucp administrative login via mail.
The default uudemon.cleanup shell script does the following:
Takes log files for individual machines from the /var/uucp/.Log directory, merges them, and places them in the /var/uucp/.Old directory with other old log information.
Removes work files (C.) seven days old or older, data files (D.) Seven days old or older, and execute files (X.) two days old or older from the spool files.
Returns mail that cannot be delivered to the sender.
Mails a summary of the status information gathered during the current day to the UUCP administrative login (uucp).
To run UUCP on a TCP/IP network, you need to make a few modifications, as described in this section.
Make sure that the following entry in /etc/inetd.conf is not preceded by a comment mark (#):
uucp stream tcp nowait root /usr/sbin/in.uucpd in.uucpd |
Entries in the /etc/uucp/Systems file should have the following fields:
System-Name Time TCP Port networkname Standard-Login-Chat
A typical entry would look like this:
rochester Any TCP - ur-seneca login: Umachine password: xxx |
Notice that the networkname field permits you to specify explicitly the TCP/IP host name. This is important for some sites. In the example above, the site has the UUCP node name rochester is different from its TCP/IP host name ur-seneca. Moreover, there could easily be a completely different machine running UUCP that has the TCP/IP host name of rochester.
The Port field in the Systems file should have the entry -. This is equivalent to listing it as uucp. In almost every case, the networkname is the same as the system name, and the Port field is -, which says to use the standard uucp port from the services database. The in.uucpd daemon expects the remote machine to send its login and password for authentication, and it prompts for them much as getty and login do.
The following entry in /etc/inet/services sets up a port for UUCP:
uucp 540/tcp uucpd # uucp daemon |
You should not have to change the entry. However, if your machine runs NIS or NIS+ as its name service, you should change the /etc/nsswitch.conf entry for /etc/services to check files first, then check nis or nisplus.
After you have set up UUCP, maintenance is straightforward. This section explains ongoing UUCP tasks with regard to security, maintenance, and troubleshooting.
The default /etc/uucp/Permissions file provides the maximum amount of security for your UUCP links. The default Permissions file contains no entries.
You can set additional parameters for each machine to define:
Ways it can receive files from your machine
Directories for which it has read and write permission
Commands it can use for remote execution
A typical Permissions entry is:
MACHINE=datsun LOGNAME=Udatsun VALIDATE=datsun COMMANDS=rmail REQUEST=yes SENDFILES=yes |
This entry allows files to be sent and received (to and from the "normal" UUCP directories, not from anywhere in the system) and causes the UUCP user name to be validated at login time.
UUCP does not require much maintenance. Apart from making sure that the crontab file is in place, as described in the section "uudemon.poll Shell Script", all you have to worry about is the growth of mail files and the public directory.
All email messages generated by the UUCP programs and scripts go to the user ID uucp. If you do not log in frequently as that user, you might not realize that mail is accumulating (and consuming disk space). To solve this, make an alias in /etc/aliases and redirect that email either to root or to yourself and others responsible for maintaining UUCP. Don't forget to run the newaliases command after modifying the aliases file.
The directory /var/spool/uucppublic is the one place in every system to which UUCP by default is able to copy files. Every user has permission to change to /var/spool/uucppublic and read and write files in it. However, its sticky bit is set, so its mode is 01777. As a result, users cannot remove files that have been copied to it and that belong to uucp. Only you, as UUCP administrator logged in as root or uucp, can remove files from this directory. To prevent the uncontrolled accumulation of files in this directory, you should make sure to clean it up periodically.
If this is inconvenient for users, encourage them to use uuto and uupick rather than removing the sticky bit, which is set for security reasons. (See the uuto(1C) man page for instructions for using uuto and uupick.) You can also restrict the mode of the directory to only one group of people. If you do not want to run the risk of someone filling your disk, you can even deny UUCP access to it.
These procedures describe how to solve common UUCP problems.
You can check if the modems or other ACUs are not working properly in several ways.
Run uustat -q. This will give counts and reasons for contact failure.
Run cu -d -lline, where line is /dev/cua/a. This lets you call over a particular line and print debugging information on the attempt. The line must be defined as direct in the /etc/uucp/Devices file. (You must add a telephone number to the end of the command line if the line is connected to an autodialer or the device must be set up as direct.)
Verify that you have up-to-date information in your Systems file if you are having trouble contacting a particular machine. Some things that might be out of date for a machine are its:
If you cannot contact a particular machine, you can check out communications to that machine with Uutry and uucp.
To try to make contact, type /usr/lib/uucp/Uutry -r machine and press Return.
Replace machine with the host name of the machine you are having problems contacting. This command:
Starts the transfer daemon (uucico) with debugging. You can get more debugging information if you are root.
Directs the debugging output to /tmp/machine.
Prints the debugging output to your terminal (tail -f).
Press Control-c to end output. You can copy the output from /tmp/machine if you want to save it.
If Uutry doesn't isolate the problem, try to queue a job by typing uucp --r file machine\!/dir/file and press Return.
Replace file by the file you want to transfer, machine by the machine you want to copy to, and /dir/file where the file will be placed on the other machine. The r option queues a job but does not start the transfer.
Now use Uutry again.
If you still cannot solve the problem, you might need to call your local support representative. Save the debugging output; it will help diagnose the problem.
You might also want to decrease or increase the level of debugging provided by Uutry through the -x n option, where n indicates the debug level. The default debug level for Uutry is 5.
Debug level 3 provides basic information as to when and how the connection is established, but not much information about the transmission itself. Debug level 9, on the other hand, provides exhaustive information about the transmission process. Be aware that debugging occurs at both ends of the transmission. If you intend to use a level higher than 5 on a moderately large text, get in touch with the administrator of the other site and agree on a time for doing so.
UUCP has two types of error messages: ASSERT and STATUS.
When a process is aborted, ASSERT error messages are recorded in /var/uucp/.Admin/errors. These messages include the file name, sccsid, line number, and text. These messages usually result from system problems.
STATUS error messages are stored in the /var/uucp/.Status directory. The directory contains a separate file for each remote machine your computer attempts to communicate with. These files contain status information on the attempted communication and whether it was successful.
Several commands are available for checking basic networking information:
uuname - Use this command to list those machines your machine can contact.
uulog - Use this command to display the contents of the log directories for particular hosts.
uucheck -v - Run this command to check for the presence of files and directories needed by uucp. This command also checks the Permissions file and outputs information on the permissions you have set up.
This section lists the error messages associated with UUCP.
Table 13-1 lists ASSERT error messages.
Table 13-1 ASSERT Error Messages
Table 13-2 is a list of the most common STATUS error messages.
Table 13-2 UUCP STATUS Messages
Error Message |
Description/Action |
---|---|
Status is okay. |
|
There is currently no device available for the call. Check to see that there is a valid device in the Devices file for the particular system. Check the Systems file for the device to be used to call the system. |
|
A call was placed to the system at a time other than what is specified in the Systems file. |
|
Self-explanatory. |
|
The login for the given machine failed. It could be a wrong login or password, wrong number, a very slow machine, or failure in getting through the Dialer-Token-Pairs script. |
|
The conversation failed after successful startup. This usually means that one side went down, the program aborted, or the line (link) was dropped. |
|
The remote machine never answered. It could be a bad dialer or the wrong phone number. |
|
The machine called us with a login/machine name that does not agree with the Permissions file. This could be an attempt to masquerade!. |
|
The calling device to be used is currently locked and in use by another process. |
|
An ASSERT error occurred. Check the /var/uucp/.Admin/errors file for the error message and refer to the section "UUCP Error Messages". |
|
The system is not in the Systems file. |
|
The device tried does not exist or the modes are wrong. Check the appropriate entries in the Systems and Devices files. |
|
The device could not be opened. |
|
The called machine is reporting a different name than expected. |
|
The called machine requires that it calls your machine. |
|
The remote machine has a LCK file for your machine. It could be trying to call your machine. If it has an older version of UUCP, the process that was talking to your machine might have failed, leaving the LCK file. If it has the new version of UUCP and is not communicating with your machine, then the process that has a LCK file is hung. |
|
The remote machine does not have the node name of your machine in its Systems file. |
|
The login used by your machine to login does not agree with what the remote machine was expecting. |
|
The remote machine rejected the communication with your machine for an unknown reason. The remote machine might not be running a standard version of UUCP. |
|
Login succeeded, but initial handshake failed. |
|
This is usually the same as DIAL FAILED. However, if it occurs often, suspect the caller script in the Dialers file. Use Uutry to check. |
Table 13-3 lists the exit code numbers of error status messages produced by the /usr/include/sysexits.h file. Not all are currently used by uucp.
Table 13-3 UUCP Error Messages by Number
Message Number |
Description |
Meaning |
---|---|---|
64 |
Base value for error messages |
Error messages begin at this value. |
64 |
Command Line Usage Error |
The command was used incorrectly, for example, with the wrong number of arguments, a bad flag, or a bad syntax. |
65 |
Data Format Error |
The input data was incorrect in some way. This should only be used for user's data and not system files. |
66 |
Cannot Open Input |
An input file (not a system file) did not exist, or was not readable. This could also include errors like "No message" to a mailer (if it cared to catch it). |
67 |
Address Unknown |
The user specified did not exist. This might be used for mail addresses or remote logins. |
68 |
Host Name Unknown |
The host did not exist. This is used in mail addresses or network requests. |
69 |
Service Unavailable |
A service is unavailable. This can occur if a support program or file does not exist. This message also can be a catchall message when something doesn't work and you don't know why. |
70 |
Internal Software Error |
An internal software error has been detected. This should be limited to non-operating system related errors if possible. |
71 |
System Error |
An operating system error has been detected. This is intended to be used for conditions like "cannot fork","cannot create pipe." For instance, it includes getuid returning a user that does not exist in the passwd file. |
72 |
Critical OS File Missing |
Some system file like /etc/passwd or /etc/utmp does not exist, cannot be opened, or has some error such as syntax error. |
73 |
Can't Create Output File |
A user specified output file cannot be created. |
74 |
Input/Output Error |
An error occurred while doing I/O on some file. |
75 |
Temporary Failure. User is invited to retry |
Temporary failure, indicating something that is not really an error. In sendmail, this means that a mailer, for example, could not create a connection, and the request should be reattempted later. |
76 |
Remote Error in Protocol |
The remote system returned something that was "not possible" during a protocol exchange. |
77 |
Permission Denied |
You do not have sufficient permission to perform the operation. This is not intended for file system problems, which should use NOINPUT or CANTCREAT, but rather for higher level permissions. For example, kre uses this to restrict students who can send mail to. |
78 |
Configuration Error |
There is an error in the configuration. |
79 |
Entry Not Found |
Entry not found. |
79 |
Maximum Listed Value |
Highest value for error messages. |