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Net::Config

Section: Perl Programmers Reference Guide (3)
Updated: 2001-09-21
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NAME

Net::Config - Local configuration data for libnet  

SYNOPSYS

    use Net::Config qw(%NetConfig);

 

DESCRIPTION

"Net::Config" holds configuration data for the modules in the libnet distribuion. During installation you will be asked for these values.

The configuration data is held globally in a file in the perl installation tree, but a user may override any of these values by providing their own. This can be done by having a ".libnetrc" file in their home directory. This file should return a reference to a HASH containing the keys described below. For example

    # .libnetrc
    {
        nntp_hosts => [ "my_prefered_host" ],
        ph_hosts   => [ "my_ph_server" ],
    }
    __END__

 

METHODS

"Net::Config" defines the following methods. They are methods as they are invoked as class methods. This is because "Net::Config" inherits from "Net::LocalCfg" so you can override these methods if you want.
requires_firewall HOST
Attempts to determine if a given host is outside your firewall. Possible return values are.

  -1  Cannot lookup hostname
   0  Host is inside firewall (or there is no ftp_firewall entry)
   1  Host is outside the firewall

This is done by using hostname lookup and the "local_netmask" entry in the configuration data.

 

NetConfig VALUES

nntp_hosts
snpp_hosts
pop3_hosts
smtp_hosts
ph_hosts
daytime_hosts
time_hosts
Each is a reference to an array of hostnames (in order of preference), which should be used for the given protocol
inet_domain
Your internet domain name
ftp_firewall
If you have an FTP proxy firewall (NOT an HTTP or SOCKS firewall) then this value should be set to the firewall hostname. If your firewall does not listen to port 21, then this value should be set to "hostname:port" (eg "hostname:99")
ftp_firewall_type
There are many different ftp firewall products available. But unfortunately there is no standard for how to traverse a firewall. The list below shows the sequence of commands that Net::FTP will use

  user        Username for remote host
  pass        Password for remote host
  fwuser      Username for firewall
  fwpass      Password for firewall
  remote.host The hostname of the remote ftp server

0
There is no firewall
1
     USER user@remote.host
     PASS pass

2
     USER fwuser
     PASS fwpass
     USER user@remote.host
     PASS pass

3
     USER fwuser
     PASS fwpass
     SITE remote.site
     USER user
     PASS pass

4
     USER fwuser
     PASS fwpass
     OPEN remote.site
     USER user
     PASS pass

5
     USER user@fwuser@remote.site
     PASS pass@fwpass

6
     USER fwuser@remote.site
     PASS fwpass
     USER user
     PASS pass

7
     USER user@remote.host
     PASS pass
     AUTH fwuser
     RESP fwpass

ftp_ext_passive
ftp_int_pasive
FTP servers normally work on a non-passive mode. That is when you want to transfer data you have to tell the server the address and port to connect to.

With some firewalls this does not work as the server cannot connect to your machine (because you are behind a firewall) and the firewall does not re-write the command. In this case you should set "ftp_ext_passive" to a true value.

Some servers are configured to only work in passive mode. If you have one of these you can force "Net::FTP" to always transfer in passive mode; when not going via a firewall, by setting "ftp_int_passive" to a true value.

local_netmask
A reference to a list of netmask strings in the form "134.99.4.0/24". These are used by the "requires_firewall" function to determine if a given host is inside or outside your firewall.

The following entries are used during installation & testing on the libnet package

test_hosts
If true then "make test" may attempt to connect to hosts given in the configuration.
test_exists
If true then "Configure" will check each hostname given that it exists

$Id: //depot/libnet/Net/Config.pm#17 $


 

Index

NAME
SYNOPSYS
DESCRIPTION
METHODS
NetConfig VALUES




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