10 UNIX-to-UNIX Copy Program

The UNIX-to-UNIX Copy Program (UUCP) is a group of programs that enables batched, error-free file transfer and remote command execution between two UNIX systems. UUCP is typically used to transfer electronic mail, network nets, and public domain software over low-speed, low-cost communications links. Tru64 UNIX implements the HoneyDanBer version of UUCP.

This chapter describes:

The UUCP Environment

How to configure your system for UUCP

How to manage UUCP

For general information about UUCP see uucp_intro(7). For information on how to use UUCP, see the Command and Shell User's Guide.

For troubleshooting information, see Section 14.12.

10.1 UUCP Environment

In the UUCP environment, systems can be connected to each other in the following ways:

Directly connected to each other, if they are in close proximity

Connected through modems and a telephone network, if they are not in close proximity

Connected through a local area network (LAN), if they are not in close proximity

Figure 10-1 shows two simple UUCP configurations. Figure 10-2 shows a sample UUCP configuration on a LAN in which Host A has a TCP/IP connection with Host C.

Figure 10-1: Sample Simple UUCP Configuration

Figure 10-2: Sample UUCP Over TCP/IP Configuration

10.2 Planning UUCP

This section describes those tasks you need to do before configuring UUCP.

10.2.1 Verifying the Correct Hardware

In verifying the correct hardware, you are verifying both the cables and modems, if used.

Make sure you are using the correct cable to connect to the serial port of your system. If you do not, you might experience signal degradation and the software will fail to function properly.

If the two systems are in close proximity to each other, use one of the null modem cables listed in Table 5-1.

If the two systems are connected through modems and telephone lines, see Table 5-7 for a list of modem cables to use. When using modems with UUCP, make sure that both the local and the remote modems are correctly configured.

UUCP can also be configured to run over TCP/IP local area networks (LANs). For information on running UUCP over a LAN, see uucp_manual_setup(7).

10.2.2 Preparing for the Configuration

UUCP configuration consists of the following parts:

Defining connection information for your system

Defining dial-up information for outgoing calls

Defining information for receiving incoming calls

The type of information you need depends on the types of connections you plan to set up and use. The following sections contain worksheets that you can use to record the information required to configure UUCP.

10.2.2.1 Information for Connections

Figure 10-3 shows the UUCP Setup Worksheet. If you are viewing this manual online, you can use the print feature to print a copy of the worksheet. The sections that follow explain the information you need to record on the worksheet.

Figure 10-3: UUCP Setup Worksheet

Type of connection

The types of connections you want to configure. You can configure one or all of the following connections:

Modems -- Modems enable you to use UUCP over analog transmission facilities, which include telephone lines.

Direct (hardwired) links -- Direct hardwired links connect systems with cables.

TCP/IP -- Connections using the TCP/IP protocol.

For modem connections, supply the following information:

Modem type

The type of modem you want to use. The supported devices are listed in the /usr/lib/uucp/Devices file. For more information, see uucp_manual_setup(7).

Baud rate

The speed at which the modem is to operate; for example: 1200, 2400, 9600, or any.

Device name

The name of the tty device that you want the modem to use, as listed in the /dev directory. If you are unsure of the terminal device, see ports(7).

/etc/inittab entry ID

The process ID for the uugetty process entry in the /etc/inittab file. The uugetty process sets up speed, terminal flags, and the line discipline for managing terminals. For more information, see uugetty(8).

Note

You should run the uugetty command only on RS-232 lines, not printer or console lines.

For direct link connections, supply the following information:

Remote system name or Direct

The type of direct link. If you want to connect to a specific remote system, enter the name of the remote system. This restricts connections to that system only.

If you want to connect to any system to which you have a direct hardwired connection, check Direct.

Baud rate

The speed at which the direct link is to operate; for example: 1200, 2400, or 9600.

Device name

The name of the tty device that you want the direct link to use, as listed in the /dev directory. If you are unsure of the terminal device, see ports(7).

/etc/inittab entry ID

The process ID for the uugetty process entry in the /etc/inittab file. The uugetty process sets up speed, terminal flags, and the line discipline for managing terminals. For more information, see uugetty(8).

Note

You should run the uugetty command only on RS-232 lines, not printer or console lines.

For TCP/IP connections, supply the following information:

Outgoing connections

If you want to configure UUCP to place outgoing calls over TCP/IP, check Yes. When you enable UUCP to place outgoing calls over TCP/IP, an entry for TCP/IP is added to the /usr/lib/uucp/Devices file.

Otherwise, check No.

Incoming connections

If you want to configure UUCP to accept incoming calls over TCP/IP, check Yes. When you enable UUCP to accept incoming calls over TCP/IP, the /etc/inetd.conf file is modified. In addition, you must stop and restart the inetd daemon to be able to accept UUCP calls over TCP/IP.

Otherwise, check No.

10.2.2.2 Information for Outgoing Systems

Figure 10-4 shows the UUCP Outgoing Systems Worksheet. If you are viewing this manual online, you can use the print feature to print a copy of the worksheet. The sections that follow explain the information you need to record on the worksheet.

Figure 10-4: UUCP Outgoing Systems Worksheet

Remote system name

The name of the remote system to which you plan to connect.

Mode of connection

The mode of the connection. Check modem, direct hardwired, or TCP/IP. You must configure the mode of the connection with the information from Section 10.2.2.1.

TCP/IP conversation protocol

For TCP/IP connections, the TCP/IP conversation protocol, which can be one of the following:

g -- Specifies to use the default protocol, which provides error checking.

t -- Presumes an error-free channel and therefore is not reliable for use with modem connections.

e -- Used to communicate with sites that are running both Tru64 UNIX and other UNIX versions of UUCP.

f -- Relies on flow control of the data stream. It is meant for working over links that can virtually be guaranteed to be error free, specifically X.25/PAD links.

Calling times

The times when your system is allowed to connect to the remote host. You can select the following times:

Any time of any day

Evenings -- Monday to Friday 5 p.m. to 8 a.m.; Saturday and Sunday, all day

Any three nights -- You can choose the three nights from the following:
- Monday to Friday, 11 p.m. to 8 a.m.
- Saturday, all day
- Sunday, until 5 p.m.

Never

Baud rate or Any

The baud rate that corresponds to a device you configured in the /usr/lib/uucp/Devices file, or you can specify any, if the device can be used at any speed.

Phone number (for modem)

For modem connections, the telephone number of the remote system. You can enter the complete telephone number or a dialing prefix and the telephone number.

A dialing prefix is defined in the /usr/lib/uucp/Dialcodes file. The /usr/lib/uucp/Dialcodes file contains dial code abbreviations and partial phone numbers that complete the telephone entries in the /usr/lib/uucp/Systems file. Entries in the /usr/lib/uucp/Dialcodes file contain an alphabetic prefix attached to a partial phone number that can include, for example, access codes, area codes, and exchange numbers.

If you know the dialing prefix, enter it on the worksheet. If none is defined, enter it and the sequence of numbers to be associated with the prefix.

Login ID

The login name for your system on the remote system. This must match the information in the /etc/passwd file on the remote system. Ask the administrator of the remote system for the login name and password that is assigned to your system on the remote system. The administrator of the remote system must include the login name and password for your system in the remote system's /etc/passwd file.

Note

Although the password for the login ID on the remote system is required in order to configure UUCP, to protect system security do not write the password on this worksheet.

For modem/direct links, expect-send string

The expect-send string to be used immediately before performing the login on the remote system. You can choose one of the following:

To send a series of carriage returns before expecting any characters from the remote system

To specify no expect-send strings

To be prompted to enter expect-send strings

Modems usually use a series of carriage returns as an expect-send string.

For more information on expect-send strings, see Systems(4).

10.2.2.3 Information for Incoming Systems

Figure 10-5 shows the UUCP Incoming Systems Worksheet. If you are viewing this manual online, you can use the print feature to print a copy of the worksheet. The sections that follow explain the information you need to record on the worksheet.

Figure 10-5: UUCP Incoming Systems Worksheet

If you are viewing this manual online, you can use the print feature to print a copy of this part of the worksheet. The sections that follow explain the information you need to record on the worksheet.

Remote system name

The name of the remote system you want to allow to establish incoming UUCP connections.

Local system name

The name of your system. The default provided is the name that you assigned your system at installation.

Login ID

The login ID for the remote system. The login ID is automatically added to the /etc/passwd file on your system.

By convention, the login ID that you assign to a remote system establishing incoming connections is the system name prefixed with an uppercase u (U). For example, if you specify machine1 for incoming connections, the login ID, by convention, is Umachine1; however, you can select any login ID.

You also have the option of adding a comment to the /etc/passwd file for this login ID.

You have the option to assign more than one login ID for each incoming system. Assigning multiple logins to a remote system allows you to maintain better access control for users on the remote system. With multiple logins, you can grant privileged users on the remote system more access on your system than you do to nonprivileged users. With multiple logins, you can assign multiple sets of permissions.

You must provide this information to the administrator of each remote system that will connect to your system as an incoming system.

REQUEST option

If you want a remote system to ask for any queued work on the local system that is meant for that remote system, check Yes; otherwise, check No.

If you check Yes, remote system users can transfer files to and execute commands on a local system more easily. If security is a consideration, you can restrict this access so that the local system retains control of file transfers and command executions initiated by remote systems.

SENDFILES option

If you want the local system to try to send queued work to the calling remote system after the remote computer finishes transferring files to or executing commands on the local system, check Yes; otherwise, check No.

Security considerations at your site might require that you limit a remote system's access to the local system by using the default value CALL for this option.

Additional READ/WRITE locations

If you do not specify pathnames in the READ and WRITE options, uucp permits files to be transferred only to the /usr/spool/uucppublic directory. However, if you specify pathnames in these options, you must enter the pathname for every source and destination. If you enter a pathname in either option, you must also explicitly specify the public directory if you want the uucico daemon to be allowed to place files in that location.

Additional NOREAD/NOWRITE locations

These options allow you to explicitly specify directories and files on the local system to which the remote system cannot transfer data. These are exceptions to the READ and WRITE options.

Commands

A list of commands the remote system is allowed to run on the local system. If you list a set of commands, that list comprises the new default command set for the systems listed in the MACHINE entry of the /usr/lib/uucp/Permissions file. The default is the command rmail only.

VALIDATE option

If you want the calling remote system to use a specific ID and password, check Yes; otherwise, check No.

If you use this option, no other ID from the remote system can call in. Several systems, however, can use the same ID. The VALIDATE option is meaningful only when the login ID and password are protected.

CALLBACK option

If you want the local system to contact the remote system before the remote system can transfer any files to the local system, check Yes; otherwise, check No.

If both systems use the CALLBACK option in their respective Permissions files, they will never be able to communicate with each other.

Phone number (modems only)

For modem connections, the phone number and speed of the modem attached to the local system. You must provide this information to the administrator of each remote system that will connect to your system as an incoming system.

10.3 Configuring UUCP

After you complete the required UUCP planning, use the uucpsetup script to configure UUCP. To invoke the uucpsetup script, log in as superuser and either choose the UNIX-to-UNIX Copy Program (UUCP) option from the Setup Menu or enter the following command:

# /usr/sbin/uucpsetup

The uucpsetup script prompts you for information required to configure connections, incoming systems, and outgoing systems.

Table 10-1 summarizes the various uucpsetup command syntaxes:

Table 10-1: Additional uucpsetup Commands

Use this command:	If you want to:
`uucpsetup`	Configure connections, incoming systems, and outgoing systems
`uucpsetup -i`	Configure the incoming systems only
`uucpsetup -m`	Modify UUCP connections
`uucpsetup -o`	Configure the outgoing systems only
`uucpsetup -p`	Configure the `Poll` file

For information about other options, see uucpsetup(8).

The following sections provide information on how to configure connections, incoming systems, outgoing systems, and the Poll file.

10.3.1 Configuring Connections

After you invoke uucpsetup, use the the information you gathered in Section 10.2.2.1 to configure UUCP connections. The following guidelines explain how to answer some of the script questions:

Device names -- The script lists the available device names. Enter the last letter or number of the device that you want the modem to use. For example, if you want to use tty01, enter 1.

/etc/inittab entry ID -- The script prompts you for the Identifier field and asks if this entry will be used in shared mode. It automatically supplies information for the other fields. No two processes can have the same ID.
The following example illustrates how to select the process ID (PID) u4:
```
Select an ID for the process in /etc/inittab file
For example type 'u1': u4
```
The ID that you select is checked against those that exist in the /etc/inittab file. If the ID that you assign exists, the uucpsetup script prompts you to enter another ID.
You must also indicate whether the system will use the modem or direct line in shared mode.
For more information on the /etc/inittab file, see inittab(4).

10.3.2 Configuring Outgoing Systems

After you invoke the uucpsetup script, use the the information you gathered in Section 10.2.2.2 to configure UUCP for outgoing systems. This enables you to use UUCP to connect to other remote systems.

If you are doing a complete UUCP setup, the uucpsetup script prompts you for information on outgoing systems when you finish configuring connections. The following guidelines explain how to answer some of the script questions:

Phone number -- If you choose a dialing prefix and the telephone number, the script prompts you to enter a prefix to be defined in the /usr/lib/uucp/Dialcodes file. After you enter the prefix, the script prompts you for the meaning of the prefix. Enter the sequence of numbers that you want the system to substitute for the prefix. The following example illustrates how to define the prefix btown to be the dialing sequence 1617772:
```
Enter the prefix for the Dialcodes file; for example "boston"
       stands for 9=16171234 : btown
What telephone number does the prefix stand for; Please include
       the long distance access code, area, or country codes;
       for example type 9=1617123 : 9=1617772
```
The 9 in this example is used to obtain a secondary dial tone. The 9 is site specific; it can be different for your site. The equal sign (=) is used with the 9, or number for your site, and means "wait for the dial tone." Following the equal sign (=) is the rest of the number. Enter the rest of the number.

Password -- For security considerations, the password is not written on the worksheet. However, when the script prompts for it, you must enter it.

If you define an outgoing TCP system, edit the /etc/uucp/Systems file and add an entry for the remote system. The remote system name must be the fully qualified name.

10.3.3 Configuring Incoming Systems

After you invoke the uucpsetup script, use the the information you gathered in Section 10.2.2.3 to configure UUCP for incoming systems. This enables specific remote systems to connect to your system using UUCP.

If you are doing a complete UUCP setup, the script prompts you for information on incoming systems when you are done configuring outgoing systems.

The first time you add an incoming system, the Incoming Systems Configuration menu prompts you for the name of the system you want to add. After you add an incoming system, this menu offers you the following choices:

Specify a remote system name.

Specify options for all the other systems not specified in the Permissions file but listed in the Systems file.

Neither. If you choose this option, the script terminates and the defaults for the options are not entered in the Permissions file.

The following guidelines explain how to answer some of the script questions:

Password -- The uucpsetup script invokes the vipw command, which starts your default editor (defined in the EDITOR environment variable) and allows you to edit the UUCP entry for the incoming system. After you are finished editing the /etc/passwd file, save the file, exit the editor, and supply a password for the new entry. The following example shows output from this process on a system that is configured to use the vi utility as its default editor:

Invoking 'vipw'.
Press RETURN to continue...
[Return]
root:fQPPWjF20Dfso:0:1:Charles Root:/:/bin/csh
nobody:*Nologin:4294967294:4294967294:anonymous NFS user:/:
daemon:*:1:1:Mr Background,,,:/:
uucp:No Login:2:2:UNIX-to-UNIX Copy:/usr/spool/uucppublic:\
     /usr/lib/uucp/uucico
bin:*:3:4:Mr Binary:/bin:
marcy:5jW0VXKeP6n1E:1242:15:Marcy Darcy,,,:\
     /usr/users/marcy:/bin/false
Umachine1:H/kj951Fq12ub:2:2:uucp login:/usr/spool/uucppublic:\
    /usr/lib/uucp/uucico
~
~
~
"/etc/ptmp" 15 lines, 933 characters
:wq
15 password entries, maximum length 100
 
You must enter a password
Changing password for Umachine1.
New password:
Retype new password:

You must provide this information to the administrator of each remote system that will connect to your system as an incoming system.

Commands -- The script prompts you for each command separately.

If you define an incoming UUCP system and your system uses NIS, edit the /etc/passwd file and add the wildcard (+:) as the last line (if not there already).

10.3.4 Configuring the Poll File

After you invoke the uucpsetup script with the -p option, you configure the /usr/lib/uucp/Poll file by completing the following steps:

Enter 1 (Configure the Poll file) from the Poll File Configuration Menu.

Enter the name of the remote system, which has been configured in the /usr/lib/uucp/Systems file as an outgoing system.

Enter the sequence of hourly intervals. For example, to have the system polled every 4 hours, enter 0 4 8 12 16 20.
Press Return to update the Poll file.

To add another system to the Poll file, enter y; otherwise, press Return to exit uucpsetup.

10.3.5 Configuring the uucico Daemon

The uucico daemon transfers UUCP command, data, and execute files to remote systems. Both the local and remote systems run the uucico daemon, and the two daemons communicate with each other to complete transfer requests.

Typically, the uucico daemon is set up as the UUCP user's login shell for incoming connections, or it is automatically called by various UUCP commands for outgoing connections, and no further configuration is necessary. However, you might need to specify the type of flow control uucico uses for certain UUCP transfers. For example, if you establish a connection to a terminal server via a modem and then telnet to a UUCP account, you might require a different type of flow control than a user who initiates UUCP transfers via a serial port connection.

To specify the type of flow control that the uucico daemon uses, set the FLWCTL environment variable for the accounts on your system that use UUCP connections. Permitted values for FLWCTL are: HW (hardware), SW (software), HSW (hardware and software), and NONE. The local and remote systems should use the same type of flow control. If the remote site runs UUCP on a different platform, FLWCTL should be set to NONE on the Tru64 UNIX system.

For example, to establish a UUCP connection over telnet, you would set flow control to NONE as follows:


$ export FLWCTL=NONE
$ /usr/lib/uucp/uutry remote_site

On a system that is configured to allow other sites to dial in, you can use the following procedure to create a customized script that automatically sets the FLWCTL variable:

Create a file, optionally called uu_start, that contains the following commands:
```
#! /bin/ksh
export FLWCTL=NONE
exec /usr/lib/uucp/uucico $*
```

Change the permissions on the file to make it executable:
```
# chmod +x /usr/local/bin/uu_start
 
 
```

Change the UUCP account's login shell from /usr/lib/uucp/uucico to the new executable file:
```
# chsh uucp
Old shell: /usr/lib/uucp/uucico
New shell: /usr/local/bin/uu_start
```

10.4 Monitoring the File Transfer Queue

Monitoring the file transfer queue enables you to determine the status of several types of networking operations, including jobs that have been queued on a local system for transfer to a remote system. General users and system administrators can monitor the file transfer queue.

10.4.1 Getting Queue Status Manually

To get queue status manually, use the uustat -q command.

This command lists the jobs (waiting to execute or currently executing) queued for all systems. If a status file exists for a system, its date, time, and status information are reported.

The uustat command also allows you to do the following:

Get information about the status of mail activities

Control uucp jobs queued to run on remote systems

Check the status of uucp connections to other systems, using the -m flag

Cancel transfer requests, using the -k flag

Monitor requests for file transfers generated with the uucp and uuto commands, and requests for command executions generated with the uux command

See uustat(1) for more information on uustat flags.

The following example shows all jobs in the current queue: one command file for system host4, three command files for system host6, and two command files for system host8. The command files for system host6 have been in the queue for 2 days.

# uustat -q
host4 1C Sat May 9 11:12:30 1992 SUCCESSFUL
host6 3C(2) Sat May 9 11:02:35 1992 CAN'T ACCESS DEVICE
host8 2C Sat May 9 10:54:02 1992 NO DEVICES AVAILABLE

10.4.2 Getting Queue Status Automatically

You can automatically receive status information about the uucp file transfer queue. To enable this mechanism, edit the /usr/spool/cron/crontabs/uucp file and delete the comment character (#) from the beginning of the following line:

# 48 8,12,16 * * * /usr/lib/uucp/uudemon.admin > /dev/null

In the preceding example:

`48`	Represents minutes
`8,12,16`	Represents hours based on 24-hour clock notation
`* * *`	Three asterisks are placeholders representing the day of the month, the month of the year, and the day of the week

The cron daemon will run the uudemon.admin shell script daily at 48 minutes past the hours 8, 12, and 16; that is, at 8:48 a.m., 12:48 p.m., and 4:48 p.m. The uudemon.admin script sends mail to the uucp login ID containing queue status information.

Note

These times are the defaults. You can change the time to fit the needs of your site by editing the line in the /usr/spool/cron/crontabs/uucp file.

You can also manually run the uudemon.admin script. If you do, you should run it at least once a day.

10.4.3 Guidelines for Checking Queue Status

When examining queue status, check the number and age of the file-transfer and command execution requests queued in the /usr/spool/uucp/system_name directory. In some cases, queued jobs remain in the queue for some time, essentially going undelivered. The status information you need to check includes:

The age in days of the oldest request in each queue

The number of times the local system has tried and failed to reach the specified computer

The reason for the failure to contact the specified system
See Appendix E for error messages and solutions.

If necessary, delete the files in the queue, either manually or automatically. See Section 10.5 for information on deleting files.

10.5 Cleaning Up the Spooling Directories

Each system connected by UUCP has the following spooling directories:

The /usr/spool/uucp/system_name directory is the UUCP spooling directory. It contains queued local requests for file transfers and command executions on remote systems. These files are removed by the uucp program after they are transferred to the designated system.

The /usr/spool/uucppublic directory is the UUCP public directory. When a user transfers a file to a remote system or issues a request to execute a command on an other system, the files generated by these UUCP commands are stored in the public directory on the designated system.

Depending upon the size of your installation and the number of files sent to the local /usr/spool/uucppublic directory by users on remote systems, the public directory can become quite large. Similarly, if requests are not transferred to remote systems for whatever reasons, the spooling directory could also become quite large. Therefore, part of UUCP management is to clean up the spooling directories and conserve disk resources.

10.5.1 Cleaning Up Directories Manually

To clean up the spooling directories manually, do the following:

Log in as root.

Remove files by using the uucleanup command, with the following syntax:
uucleanup [options...]

The uucleanup program performs the following tasks:

Informs the system manager of requests to send files to and receive files from remote systems that the local system cannot contact.

Warns users about requests that have been waiting in the spooling directory for a given period of time. The default is 1 day.

Returns to the original sender mail that cannot be delivered.

Removes all other files older than a specified number of days from the spooling directory.

Note

Depending on the size of your installation and the available storage space on the local system, you can set the age limit for any length of time. However, you should allow files to remain in the spooling directory for at least the default number of days.

See uucleanup(8) for more information on the uucleanup command options.

The following example deletes all old files in the UUCP spooling and public directories for system host2 on the local system:


# uucleanup -shost2

10.5.2 Cleaning Up Directories Automatically

Although automatic cleanup is not enabled when UUCP is installed, you can enable it by doing the following:

Log in as root.

Edit the /usr/spool/cron/crontabs/uucp file and delete the comment character (#) from the beginning of the following line:

# 45 23 * * * ulimit 5000; /usr/lib/uucp/uudemon.cleanu > /dev/null

In the preceding example:

`45`	Represents minutes
`23`	Represents hours based on 24-hour clock notation
`* * *`	Three asterisks are placeholders representing the day of the month, the month of the year, and the day of the week

The cron daemon will start the uudemon.cleanu shell script daily at 45 minutes after hour 23; that is, at 11:45 p.m. The shell script in turn starts the uucleanup program. This time is the default. You can change the time to fit the needs of your site by editing the line in the /usr/spool/cron/crontabs/uucp file.

You can instruct the cron daemon to run the uudemon.cleanu shell script daily, weekly, or at longer intervals, depending on the number of uucico and uuxqt transactions that occur on the local system.

The uudemon.cleanu script incorporates the actions of the uucleanup program and performs the following additional tasks:

Locates and deletes empty directories and files older than 30 days from the /usr/spool/uucppublic directory. This helps keep the local file system from overflowing when users send files to the public directory. If the local system does not have enough storage space to accommodate a large /usr/spool/uucppublic directory, you can change the 30-day default to a shorter time period by modifying the uudemon.cleanu shell script.

Cleans up all the uucp spooling directories, including the public directories, unless you direct it to clean up only the directories of a specific system by issuing the uucleanup -s system_name command.

Updates archived log files, removing log information more than 2 days old. The script removes log files for individual computers from the /usr/spool/uucp/.Log directory, merges them, and places them in the /usr/spool/uucp/.Old directory, which contains old log information.

Mails a summary of the status information gathered during the current day to the UUCP login ID. You can modify the script to send status information to other login IDs, such as root.

The operating system allots UUCP a specified amount of storage space for any one log file; the number of blocks is determined by the default ulimit value. If the uudemon.cleanu script fails to execute because the ulimit value is set too low for the requirements of the local system, you should increase the value.

See uudemon(8) for more information on command options.

10.5.3 Guidelines for Removing Files

When removing files from the queue, observe the guidelines for the following files:

Execute files -- Usually, you can remove execute files that have been in the queue for at least 2 days, using either the uucleanup or uudemon.cleanu script. The execute files are still queued because the data files required to execute the specified command on the designated system were not transferred. Since data files are generally sent at the same time as execute files, the transfer probably failed at the point of destination. Execute files are named X.filename and data files are named D.filename.

Command files -- Before removing old command files, make every possible effort to establish the connection and transfer the files. You can then remove these files by using either the uucleanup or uudemon.cleanu script. Command files are named C.filename.

10.6 Viewing Log Files

The uucp program creates a log file for each remote system with which your local system communicates. Each time you use the networking utilities facility, uucp places status information about each transaction in the appropriate log file. Log file names can be in either of the following forms:

/usr/spool/uucp/.Log/daemon_name/system_name

/usr/spool/uucp/.Log/command_name/system_name

In the preceding example:

`daemon_name`	Represents either `uucico` (called by the `uucp` and `uuto` commands) or `uuxqt` (called by the `uux` command)
`command_name`	Represents either `uucp` or `uux`
`system_name`	Represents the name of the system with which your local system is communicating

To display individual log files, use the uulog command, with the following syntax:

uulog [options...]

You can use the uulog command to display a summary of uucp and uux requests by user or by system. See uulog(1) for more information on the uulog command and its options.

Instead of viewing the log files individually, you can have the uudemon.cleanu script automatically append these log files to one primary log file, and then view only the one log file.

The uudemon.cleanu script combines the uucico, uuxqt, uux, and uucp log files on a system and stores them in a directory named /usr/spool/uucp/.Old. By default, the uudemon.cleanu script saves log files that are up to 2 days old.

You can change the default by modifying the -o2 option in the following line in the uudemon.cleanu script:

uucleanup -D7 -C7 -X2 -o2 -W1

If storage space is a problem on a particular system, consider reducing the number of days that the files are kept in the individual log files. See Section 10.5.2 for information on setting up the uudemon.cleanu script.

The following command displays the log file for uucico requests for system host2:

# uulog -s host2

The following command displays the log file for uuxqt requests for system host1:

# uulog -x host1

The following command displays the last 40 lines of the file transfer log for system host6 and executes a tail -f command. Press Ctrl/C to terminate the command.


# uulog -f host6 -40

10.7 Cleaning Up sulog and cron/log Files

The following two system log files are affected by the uucp program:

The /usr/adm/sulog file contains a history of superuser (su) command usage. The uudemon entries in the /usr/spool/cron/crontabs/uucp file each use the su command.

The /usr/adm/cron/log file contains a history of all the processes generated by the cron daemon.

Both files can grow quite large over a period of time. Purge these files periodically to keep them at a reasonable size. See System Administration for information on these files.

10.8 Limiting the Number of Remote Executions

The Maxuuxqts file, located in the /usr/lib/uucp directory, limits the number of uuxqt processes running simultaneously on a local system. Typically, the file requires no configuration or maintenance unless the system on which it is installed is utilized frequently and heavily by users on remote systems.

To change the number of uuxqt processes on the system, edit the Maxuuxqts file and change the ASCII number to meet the needs of your installation; the default is 2. In general, the larger the number, the greater the potential load on the local system.

10.9 Scheduling Work in the Spooling Directory

When users issue uucp commands to copy files and execute remote commands, the files containing these work requests are queued for transfer in the local /usr/spool/uucp/system_name directory. The uucp daemon uusched schedules the transfer of these files.

10.9.1 Starting uusched Manually

To schedule jobs, start the uusched daemon by using the uusched command, with the following syntax:

uusched [options...]

The following options are available:

`-x debug_level`	Produces debugging information about the progress of the `uusched` activity. The valid range for the debugging level is 0 to 9, with a default of 5. Higher numbers produce more detailed debugging information.
`-u debug_level`	Passes the `-x debug_level` specification on to the `uucico` daemon, which then produces debugging output about the file-transport activities.

10.9.2 Starting uusched Automatically

Although you can start the uusched daemon manually, the preferred method is to start it automatically at specified intervals by using the uudemon.hour shell script, which is stored in the /usr/lib/uucp directory. The shell script, in turn, is started periodically by the cron daemon, based on instructions in the /usr/spool/cron/crontabs/uucp file.

The /usr/lib/uucp/Maxuuscheds file limits the number of remote systems that the uucico daemon can contact at any one time. This file is used in conjunction with the uusched daemon and the lock files in the /usr/spool/locks directory to determine the number of systems currently being polled.

The Maxuuscheds file requires no configuration or maintenance unless the system on which it is installed is utilized frequently and heavily by users on remote systems. You use this file to help manage system resources and load averages.

The Maxuuscheds file contains an ASCII number that you can change to meet the needs of your installation; the default is 2. In general, the larger the number, the greater the potential load on the local system.

See uusched(8) for more information on the uusched command and its options.

The following command starts the uusched daemon manually as a background process:

# /usr/lib/uucp/uusched &

10.10 Calling File Transfer Programs (uudemon.hour)

The uudemon.hour shell script is used in conjunction with the Poll file, the uudemon.poll shell script, and the /usr/spool/cron/crontabs/uucp file to initiate calls to remote systems. Specifically, uudemon.hour calls programs involved in transferring files between systems at specified hourly intervals.

You can instruct the cron daemon to run the uudemon.hour shell script at specified hourly intervals. The frequency at which you run the script depends on the amount of file transfer activity originating from the local computer.

Although the uudemon.hour shell script is not enabled when UUCP is installed, you can enable it by doing the following:

Log in as root.

Edit the /usr/spool/cron/crontabs/uucp file and delete the comment character (#) from the beginning of the following line:
```
# 25,55 * * * * /usr/lib/uucp/uudemon.hour > /dev/null
 
```
In the preceding example:

25,55 Represents minutes past the hour

* * * * Four asterisks are placeholders representing the hour interval, the day of the month, the month of the year, and the day of the week

The cron daemon will run the uudemon.hour script at 25 minutes past the hour and again at 55 minutes past the hour; for example, at 8:25 a.m. and 8:55 a.m., 9:25 a.m. and 9:55 a.m., and so on.
These times are the defaults. You can change the time to fit the needs of your site by editing the line in the /usr/spool/cron/crontabs/uucp file.

If users on the local system initiate a large number of file transfers, you might need to specify that the cron daemon should start the uudemon.hour script several times an hour. If the number of file transfers originating from the local system is low, you can probably specify a start time once every 4 hours, for example.

10.11 Polling Remote Systems (uudemon.poll)

The uudemon.poll shell script is used in conjunction with the Poll file, the uudemon.hour shell script, and the /usr/spool/cron/crontabs/uucp file to initiate calls to remote systems. The uudemon.poll shell script polls the systems listed in the /usr/lib/uucp/Poll file. In addition, it creates command files for the systems listed in the Poll file.

The time at which you run the uudemon.poll script depends on the time at which you run the uudemon.hour script. You generally schedule the polling shell script to run before the hourly script. This schedule enables the uudemon.poll script to create any required command files before the cron daemon runs the uudemon.hour script.

Although the uudemon.poll script is not enabled when UUCP is installed, you can enable it by doing the following:

Log in as root.

Edit the /usr/spool/cron/crontabs/uucp file and delete the comment character (#) from the beginning of the following line:
```
# 20,50 * * * * /usr/lib/uucp/uudemon.poll > /dev/null
 
```
In the preceding example:

20,50 Represents minutes past the hour

* * * * Four asterisks are placeholders representing the hour interval, the day of the month, the month of the year, and the day of the week

The cron daemon will run the uudemon.poll script at 20 minutes past the hour and again at 50 minutes past the hour, for example, at 8:20 a.m. and 8:50 a.m., 9:20 a.m. and 9:50 a.m., and so on.
These times are the defaults. You can change the times at which the cron daemon executes the uudemon.poll script to correspond to the times you set up for the uudemon.hour script. You should instruct the cron daemon to run the uudemon.poll script about 5 to 10 minutes before running the uudemon.hour script.