Net::Telnet::Cisco and IOS-XR

Cisco IOS-XR introduces a new prompt format that is "breaking" Net::Telnet::Cisco. Basically, the Route Processor and CPU instance is added with a colon ":" before the router hostname. I was wondering why my Telnet sessions were "failing" but the logs showed they connected and got the prompt.

I looked for an update to Net::Telnet::Cisco, but the latest version I could find was 1.10, which is what I have installed. To get around this, I used the -prompt option when calling Net::Telnet::Cisco->new() from my script.

Under the "sub new" procedure in Cisco.pm, I found the existing prompt regex (you can't miss it). I copied that code and added the new piece and passed that in when I make the Net::Telnet::Cisco->new() call via the "-prompt" option. (See Net::Telnet for more info.)

All we're doing is adding a check for the Route Processor and CPU instance and colon before the hostname - optionally, so we don't break what's currently working. This is done with the addition of:

(?:[\w.\/]+\:)?
[download]

near the beginning of the existing regex.

In your_script.pl:

use Net::Telnet::Cisco;

...

my $session = Net::Telnet::Cisco->new(
  ...
    -prompt => '/(?m:^(?:[\w.\/]+\:)?[\w.-]+\s?(?:\(config[^\)]*\))?\s
+?[\$#>]\s?(?:\(enable\))?\s*$)/'
  ...
)
[download]

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