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NAME

Net::CLI::Interact::Manual::Cookbook - Miscellaneous recipes

Windows Support

The library works just fine under native windows (i.e use something like Strawberry Perl - no need for cygwin), for Telnet, Serial and SSH connections. However one additional step is required for you to have success:

You must download the plink.exe application, and pass its filesystem location in the app parameter to new(). Do not try to use any other Telnet or SSH programs (for instance the Windows bundled telnet) - they will not work. Here's an example, if plink.exe is on your Desktop:

 my $s = Net::CLI::Interact->new(
     personality => "cisco",
     transport => "Telnet",
     (Net::CLI::Interact::Transport::is_win32() ?
         (app => "$ENV{HOMEPATH}\\Desktop\\plink.exe") : () ),
 );

Unix Support

The library works fine on most Unix platforms. It will try to use the native telnet, ssh (openssh) and cu programs for Telnet, SSH and Serial connections, respectively. If you want to use another application, pass it in the app parameter to new.

In some Unix environments there can be zombie child processes left around after running your script. If this happens, set the reap option, like so:

 my $s = Net::CLI::Interact->new(
     personality => "cisco",
     transport => "Telnet",
     connect_options => {
        reap => 1,
    },
 );

Running Commands

Simple Commands

Simply send the command you wish to execute to the session. If not already done, a connection to the device will be established automatically:

 $s->cmd('show ip int br');

Normally this matches against a default prompt, which has been discovered automatically, or set by you:

 $s->set_prompt('user_prompt');

It's also possible to pass in a custom prompt for this command only:

 $s->cmd('show ip int br', { match => qr/special prompt>$/ });

However be aware that a side effect of this is that the custom prompt becomes the new default prompt for subsequent commands or macros.

Macro Commands

Call a predefined Macro from the phrasebook using this method:

 $s->macro('write_mem');

Sometimes the Macro needs parameters:

 $s->macro('to_priv_exec', { params => ['my_password'] });

You can't really create a Macro on the fly very easily, but with suitable use of cmd(), set_prompt(), and the match option to cmd() it's possible to achieve some simple flexibility.

Reconfiguring On-the-Fly

Phrasebook

It's possible to load a new phrasebook by the following method, which must be passed at least the name of the personality:

 $s->set_phrasebook({ personality => 'ios' });

You can pass any options which the Phrasebook module itself would take.

Prompt

The current prompt can be changed by passing the name of the new Prompt as it is known by the phrasebook:

 $s->set_prompt('name');

If you want to test whether the current prompt matches a different named Prompt from the phrasebook, this method can be used:

 $s->prompt_looks_like('name');

Logging

A generic logging service is available through the $session->logger object, which is based on Log::Dispatch. You can configure the logger at startup quite easily. See the Net::CLI::Interact::Logger manual page for details of the interface (config for any option can simply be passed to Net::CLI::Interact->new()).

Destinations

The default configuration sends logging messages to standard output. Let's say you also want to append them to a log file:

 my $s = Net::CLI::Interact->new({
     log_config => {
         dispatchers => ['screen','file'],
         screen => {
             class => 'Log::Dispatch::Screen',
             min_level => 'warning',
         },
         file => {
             class => 'Log::Dispatch::File',
             min_level => 'debug',
             filename => '/var/log/myapp.log',
             mode => 'append',
             format => '[%d] %m',
         },
     },
     # etc...
 });

Note that some keys are required, such as the class and min_level but others depend on the particular class being used. See Log::Dispatch::Config for more details.

Log Levels and Categories

Each log message has a standard log level (debug, warning, etc) but also a category which is a concept local to this module. Categories allow more filtering of what is logged. Each time a message is logged through $s->logger->log(...) it has a level and category.

Messages are only emitted if they pass the specific level set for that category. In this way we can suppress messages about the transport but, for example, show messages about prompt-matching at a debug level.

You can very easily set the log level for all categories using either the set_global_log_at option to new(), or the NCI_LOG_AT environment variable.

To configure these filters, use the log_flags option together with the list of default log categories used by Net::CLI::Interact. For example:

 my $s = Net::CLI::Interact->new({
     log_flags => {
         (map {$_ => 'notice'} Net::CLI::Interact->default_log_categories()),
         dialogue => 'info',
     },
     # etc...
 });

This example would set all categories to notice level except for the dialogue category, which is set to info level to get more output (on what is sent and received by each command).

Phrasebook Libraries

You can override or add to the device command phrasebooks which ship with this distribution. To start with, check the shipped dictionary for your device's current level of support, at Net::CLI::Interact::Manual::Phasebook.

If you want to add either some prompts or macros, first read the documentation for these systems at Net::CLI::Interact::Phrasebook.

All phrasebooks can inherit from others, and this is based on their location in a filesystem tree. See the phrasebooks bundled with the Net::CLI::Interact distribution for an example of this in action.

If you wish to override a phrasebook entry, simply set add_library in your code, and then create a file at the same relative point beneath that library directory as the original version shipped with the Net::CLI::Interact module, for example "<add_library>/cisco/pixos/pixos7/my_phrases".

The file itself (my_phrases) does not have to be the same name as the original, and you can have more than one file if it helps. Only the directory is matched against your chosen personality and then all files in there, and higher in the add_library tree, and distribution library tree, are loaded.

To check what phrasebooks and prompts/macros are loaded, run your script with debug level set to notice. The easiest way to do this is by setting the environment variable NCI_LOG_AT=notice.

Phrasebook Entries

Prompts

These are nothing more than named regular expressions:

 prompt configure
     match /\(config[^)]*\)# ?$/

Macros

This example waits for the device to ask "[startup-config]?" and then responds with the text startup-config. Remember, there is an implicit match statement added at the end, which is the current prompt.

 macro copy_run_start
     send copy running-config startup-config
     match /Destination filename \[startup-config\]\?$/
     send startup-config

To send instead a "press" of the Return key (output record separator), use:

 macro write_mem
     send copy running-config startup-config
     match /Destination filename \[startup-config\]\?$/
     send ''

To instead allow the user to pass in the file name, use a sprintf format.

 macro save_to_file
     send copy running-config startup-config
     match /Destination filename \[startup-config\]\?$/
     send %s

The user must then pass a parameter to the macro call, even if it's an empty string:

 $s->macro('save_to_file', { params => ['file_name'] });
 # or
 $s->macro('save_to_file', { params => [''] });

Continuations

These are Macros which start with a match instead of a send:

 macro more_pages
     match / --More-- /
     send ' '

Note that the parameter of the send is not sent with a Return character (output record separator) appended.

When included in a macro, the continuation can be in-line, like this:

 macro show_ip_route
     send show ip route
     follow / --More-- / with ' '