NAME
    netdisco - Internal API

DESCRIPTION
    This is the inside guts of the Netdisco executable. You should be
    looking in README for how to use Netdisco.

FUNCTIONS
  Network Discovery
    discover(host)
        Discovers one device, stores its info, interfaces, and neighbors,
        and returns.

    refresh_all()
        Calls discover() for each file already in device table.

    run()
        Event loop that calls discover() as long as the @Discover_Queue has
        something in it.

    schlop(file,topo_only_flag)
        Used to start a discovery based on topography file. Will then
        proceed to do an initial mac_suck() and arp_nip() unless the
        topo_only_flag is set.

    topo_add_link([{},{}])
        Pass reference to array of hash references holding link: lines from
        manual topology info. Adds information to device_port table.

    topo_load_file(filename)
        Loads and parses manual topography file.

  Utility Functions
    add_user()
        Takes 4 optional arguments from @ARGV = (user,pw,port,admin)

        If all 4 are not there, then interactive mode is entered and prompts
        are given.

    batch_mode(name,time_too?)
        Redirects STDOUT to a log file with timestamp.

        Can be called recursively. call batch_mode_end() to return to
        previous Output.

    batch_mode_end(no_compress_flag)
        Returns control of stdout to previous value, optionally compresses
        the finished output file.

        Function returns file name of closed output file.

        Pass something as first parameter to force no compression.

    end_int_handler
    end()
        Cleanup routine that is called upon interrupt (ctrl-c) or end of
        routines.

        Prints various statistics to stdout or batch_redirect() and calls
        Netdisco::log().

    load_old_devices()
        Populates %Old_Devices with which devices are in the database.

    load_old_nodes(days)
        Populates %Old_Nodes with which nodes are in the database.

        Nodes will have to have been seen in the last DAYS days.

    parse_oui()
        Parses file oui.txt in current directory. Uses contents to stuff
        table "oui".

    timeout()
        Signal handler for SIGALARM

  SNMP Functions
    arpnip()
        Connects to device and reads its ARP cache. Then adds entries to
        "node_ip" table.

        Cheers to Jim Warner for the original arpnip.

    arpwalk()
        Visits every Layer 3 device and trys to get its ARP Cache.

        Calls arpnip() for each device.

    create_device(%args)
        All %args are passed straight through to SNMP::Info except 'Class'
        which when set turns off "AutoSpecify".

         my $dev = create_device(
                    'DestHost'     => host,
                    'Community'    => public,
                    'Version'      => 2,
                    'Retries'      => 2,
                    'Class'        => 'SNMP::Info::Layer2',
                    'VersionForce' => 1,

        Connect to a device via SNMP::Info with a given host and community
        string.

        If optional "Version" and "Class" are given, no device type
        discovery is done.

        If a more specific device type is not found -1 is returned. The
        target device is probably not a network device.

        If "VersionForce" is true, no fallback to snmpv1 will happen.

    device_root()
        Looks to see if the device has a master IP instead of the one given.
        Checks for root_ip() method, then tries to lookup the reverse entry
        for sysName.0

    find_neighbors()
        Finds all the CDP information on the device and stores the results
        in device_node.

        Adds to the @Discover_Queue

    get_device(host)
        Calls create_device() with a community string

        If cached values are stored in the database for the SNMP version and
        community strings, they are used.

        If no cached values are available, or if they fail, then the values
        from the config file are tried.

    get_device_rw(device[,version])
        Returns a SNMP::Info object for a given device, using the Read-Write
        Community Strings in the config file.

        Returns undef or -1 on error.

    get_subnets(device)
        Grab netmask and ip from device interfaces. Determine device subnets
        mathematically based upon the interface information.

    mac_getportmacs()
        Fills the global %PortMAC with MAC addresses of ports already
        discovered. This is to make sure we don't mac-suck existing ports,
        such as VLANs.

    macsuck()
        Walks forwarding table for a specific device. Gets mac addresses
        that are listed in physical ports that do not have a neighbor
        listed. If the device has VLANs, it will walk each VLAN and get the
        MAC addresses from there.

    mac_savecache({},{})
        Does two things :

        1. Checks for detected uplinks, warns of such and removes nodes on
        these uplinks from additions list

        2. Stores the found forwarding table entries to the database.

    macwalk()
        Grabs all the devices out of the database. Runs macsuck() on each
        device that has layer2 capabilites.

    port_control(switch,port,direction)
    port_switch({})
        Used to shut ports on and off and to change VLANs.

    store_device()
        Calls all the global methods and sends the results off to the
        database

    store_interfaces()
        Gets all the interface information using Table Methods in
        SNMP::Info.

        Deletes the old interface entries in device_port and puts in new
        ones.

    walk_fwtable()
        Walks the Forwarding table from the "BRIDGE-MIB" for the given
        device, and then adds MAC addresses to the "node" table.

  NetBIOS Functions
    nbtstat(host)
        Connects to node and gets NetBIOS information. Then adds entries to
        node_nbt table.

        Returns whether a node is answering netbios calls or not.

    nbtwalk()
        Visits every node and trys to get its NetBIOS information.

        Calls nbtstat() for each device.

  Maintenance Functions
    alias_clean()
        Routine to clean out devices that are now listed as aliases of
        another device. This is usually necessary after a device has been
        merged into another one.

    arp_dump(dir)
        Dumps node_ip table to files arp_current and arp_archive.

    change_device_ip(from_ip, to_ip)
        Used to move move over all the information from one device to a new
        IP address. First tries to discover new device, then proceeds to
        move over old information.

    db_clean()
        Removes all the entries in "node" that are switch ports.

        Checks for nodes on non existant ports and prints a warning

        Removes nodes that are on uplink ports.

    dev_dump()
        Dumps out the device,device_ip, and topology info from device_port
        to file 'devices'.

    expire_data(type,days,archive_only)
        "type" can be : node,device

        "days" is a positive integer number of days in which an entry has
        not been updated.

        "archive_only" for node only.

        Removes devices and nodes that haven't been updated in "days" days.
        Called from nightly() and controlled through the "expire_*"
        directives in the config file.

        Cheers to Brian Wilson for his patch for the start of this feature.

    expire_device(device,expire_nodes?)
        Removes device from the database

        Set second argument to true to remove all the connected nodes and
        their IP mappings as well.

    expire_nodes(device,archive_only,port)
        Removes entries from node and node_ip for a given device.

        Set port to limit the expiration to a specific port.

        Set archive_only to 1 to archive the nodes on the device.

    expire_nodes_subnet(subnet)
        Subnet is in CIDR format, or any other format that Postgres likes.

            192.168.0.0/24

        Runs expire_ips afterwards to cleanup.

    expire_ips()
        Expires IPs not in use in node.

         delete from node_ip where 
            mac not in
                (select mac from node) 

    mac_dump()
        Dumps the node table out to mac_current.txt and mac_archive.txt.
        Adds a day stamp, no time-stamp.

    netbios_dump()
        Dumps the node_nbt table out to netbios_current.txt and
        netbios_archive.txt. Adds a day stamp, no time-stamp.

    nightly(no_batch)
        Nightly maintance routine that creates backups of the device,node,
        and node_ip tables.

        Calls expire_data(), nmis_dump(), mac_dump(), arp_dump(),
        dev_dump(), netbios_dump(), db_clean() and VACUUM ANALYZE

    nmis_dump()
        Dumps the device table out to NMIS (http://www.sins.com.au/nmis/)
        style config file.

  Graphing Functions
    graph(no_batch)
        Creates netmap of network. Calls Netdisco::make_graph() and
        graph_each()

    graph_each(Graph_obj, name)
        Generates subgraph. Called from graph(). Calls graph_node().

        Does actual GraphViz calls.

    graph_addnode(graphviz_obj,node_ip)
        Checks for mapping settings in config file and adds node to the
        GraphViz object.

  Admin Daemon
    admin_daemon_ctl(cmd)
        start,stop,restart,status

    admin_daemon_status(pid)
        Returns 0 if daemon is not running or returns pid number if running.

        pid argument is optional, used in stop function

    admin_daemon()
        Resident copy of netdisco to handle requests from the admin panel.

    admin_daemon_pid(pid_to_write)
        If not supplied arguments, Reads pid of daemon pid from
        netdisco_daemon.pid

        If supplied arguments, writes the pid out to that file.

    admin_daemon_job(job_obj)
        Runs each job. Redirects output to data/admin/job-num-date.log
        job_obj is the sql hash object for each job.

COPYRIGHT AND LICENCE
    Changes in code from 0.92 on: Copyright (c) 2003,2004 Max Baker - All
    Rights Reserved

    Original Code: Copyright (c) 2002,2003 Regents of the University of
    California All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:

        * Redistributions of source code must retain the above copyright notice,
          this list of conditions and the following disclaimer.
        * Redistributions in binary form must reproduce the above copyright notice,
          this list of conditions and the following disclaimer in the documentation
          and/or other materials provided with the distribution.
        * Neither the name of the University of California, Santa Cruz nor the 
          names of its contributors may be used to endorse or promote products 
          derived from this software without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
    IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
    TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
    PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
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