SSH to a Cisco Switch - Processing "More" Responses

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Demonstrates connecting to a Cisco switch, entering privileged mode with the ena command, and running a command whose response is paged. Each page ends with --More-- and requires a SPACE character to request the next page.

Note: QuickShell allocates a PTY, which is what a network device console expects. The device presents an interactive prompt, and each command's output is read up to the next prompt.

<?php

$success = 0;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  Demonstrates connecting to a Cisco switch, entering privileged mode, and running a command
//  whose response is paged -- each page ends with "--More--" and requires a SPACE character to
//  request the next page.

$ssh = new COM("Chilkat.Ssh");

$port = 22;
$success = $ssh->Connect('172.16.16.100',$port);
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

//  Normally you would not hard-code the password in source.  You should instead obtain it
//  from an interactive prompt, environment variable, or a secrets vault.
$password = 'mySshPassword';

$success = $ssh->AuthenticatePw('mySshLogin',$password);
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

$channelNum = $ssh->QuickShell();
if ($channelNum < 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

//  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
//  which means no limit -- without it, this call waits forever if the received data never
//  contains a match.
$ssh->ReadTimeoutMs = 15000;

$caseSensitive = 1;

//  In unprivileged mode the switch prompt ends with ">".
$success = $ssh->ChannelReceiveUntilMatch($channelNum,'>','utf-8',$caseSensitive);
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

$received = $ssh->getReceivedText($channelNum,'utf-8');
if ($ssh->LastMethodSuccess == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

print $received . "\n";

//  Send "ena" to enter privileged mode.  Cisco devices expect a bare CR to terminate a command.
$success = $ssh->ChannelSendString($channelNum,'ena\r','utf-8');
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

$success = $ssh->ChannelReceiveUntilMatch($channelNum,'Password:','utf-8',$caseSensitive);
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

$received = $ssh->getReceivedText($channelNum,'utf-8');
if ($ssh->LastMethodSuccess == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

print $received . "\n";

//  The enable password is separate from the login password, and likewise should come from a
//  secure source rather than being hard-coded.
$enablePassword = 'myEnablePassword';
$success = $ssh->ChannelSendString($channelNum,$enablePassword,'utf-8');
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

$success = $ssh->ChannelSendString($channelNum,'\r','utf-8');
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

//  In privileged mode the prompt ends with "#" instead of ">".
$success = $ssh->ChannelReceiveUntilMatch($channelNum,'#','utf-8',$caseSensitive);
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

$received = $ssh->getReceivedText($channelNum,'utf-8');
if ($ssh->LastMethodSuccess == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

print $received . "\n";

//  Run a command whose output is delivered a page at a time.
$success = $ssh->ChannelSendString($channelNum,'show running-config\r','utf-8');
if ($success == 0) {
    print $ssh->LastErrorText . "\n";
    exit;
}

//  Each read ends either at the device prompt (output complete) or at "--More--" (another page
//  is waiting).  Match the full prompt rather than a bare "#", because "#" also appears inside
//  configuration text and would match too early.
$saMatch = new COM("Chilkat.StringArray");
$saMatch->Append('MySwitchName#');
$saMatch->Append('--More--');

$sbReceived = new COM("Chilkat.StringBuilder");
$moreComing = 1;

while ($moreComing) {
    $success = $ssh->ChannelReceiveUntilMatchN($channelNum,$saMatch,'utf-8',$caseSensitive);
    if ($success == 0) {
        print $ssh->LastErrorText . "\n";
        exit;
    }

    $sbReceived->Clear();
    $pageText = $ssh->getReceivedText($channelNum,'utf-8');
    if ($ssh->LastMethodSuccess == 0) {
        print $ssh->LastErrorText . "\n";
        exit;
    }

    $sbReceived->Append($pageText);
    print $pageText . "\n";

    //  If this page ended with "--More--", send a SPACE to request the next page.
    $moreComing = $sbReceived->Contains('--More--',$caseSensitive);
    if ($moreComing) {
        $success = $ssh->ChannelSendString($channelNum,' ','utf-8');
        if ($success == 0) {
            print $ssh->LastErrorText . "\n";
            exit;
        }

    }

}

$ssh->Disconnect();

?>