Tcl

SSH to Cisco Switch - Processing "More" Responses

See more SSH Examples

Demonstrates connecting to a Cisco switch, running a command to enable privileged mode, then running a command to get a paged response requiring the SPACE char to be sent to process "--More--". Tcl

load ./chilkat.dll

set success 0

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

set ssh [new_CkSsh]

set success [CkSsh_Connect $ssh "SSH_SERVER_DOMAIN_OR_IP_ADDRESS" 22]
if {$success != 1} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# Authenticate using login/password:
set success [CkSsh_AuthenticatePw $ssh "myLogin" "myPassword"]
if {$success != 1} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# Start a shell session.
set channelNum [CkSsh_QuickShell $ssh]
if {$channelNum < 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# If the CISCO switch returns a prompt with ">", then read until we get the prompt.
# (It's not actually required that we do this, but it helps to know that all is OK at this point..)
set success [CkSsh_ChannelReceiveUntilMatch $ssh $channelNum ">" "utf-8" 1]
if {$success != 1} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# Show what we received so far:
puts [CkSsh_getReceivedText $ssh $channelNum utf-8]

# Send the "ena" command to enable privileged mode.
# (For the Cisco switch, terminate command with a single CR char.)
set success [CkSsh_ChannelSendString $ssh $channelNum "ena\r" "utf-8"]
# Assume success for this example to make it shorter..

# Read to the "Password:" prompt.
set success [CkSsh_ChannelReceiveUntilMatch $ssh $channelNum "Password:" "utf-8" 1]
if {$success != 1} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# Show what we received...
puts [CkSsh_getReceivedText $ssh $channelNum utf-8]

# Send the password.
set success [CkSsh_ChannelSendString $ssh $channelNum "MY_PASSWORD_FOR_ELEVATED_PRIVILEGE\r" "utf-8"]

# The prompt now changes from "Something>" to "Something#>
# Read until the new prompt..
set success [CkSsh_ChannelReceiveUntilMatch $ssh $channelNum "#" "utf-8" 1]
if {$success != 1} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# Show what we received...
puts [CkSsh_getReceivedText $ssh $channelNum utf-8]

# Send the "show running-config" command.
# The response will be in multiple pages, each ending with "--More--" and requiring a SPACE bar to be sent
# to get the next page.
set success [CkSsh_ChannelSendString $ssh $channelNum "show running-config\r" "utf-8"]

# Consume the response until we end with another prompt.
set saMatch [new_CkStringArray]

# Change "YOUR_PROMPT" to your actual prompt.  We don't want to check for only "#" because
# it's not specific enough.  The data in the response could contain the "#" char...
CkStringArray_Append $saMatch "YOUR_PROMPT#"
CkStringArray_Append $saMatch "--More--"

set sbReceived [new_CkStringBuilder]

set moreComing 1
while {$moreComing == 1} {

    set success [CkSsh_ChannelReceiveUntilMatchN $ssh $channelNum $saMatch "utf-8" 1]
    if {$success != 1} then {
        puts [CkSsh_lastErrorText $ssh]
        delete_CkSsh $ssh
        delete_CkStringArray $saMatch
        delete_CkStringBuilder $sbReceived
        exit
    }

    set moreComing 0

    CkStringBuilder_Clear $sbReceived
    CkStringBuilder_Append $sbReceived [CkSsh_getReceivedText $ssh $channelNum "utf-8"]

    puts [CkStringBuilder_getAsString $sbReceived]

    if {[CkStringBuilder_Contains $sbReceived "--More--" 1] == 1} then {
        set moreComing 1

        # Send a SPACE char just as if we were interactively pressing the SPACE key to get more output.
        set success [CkSsh_ChannelSendString $ssh $channelNum " " "utf-8"]
    }

}

CkSsh_Disconnect $ssh

delete_CkSsh $ssh
delete_CkStringArray $saMatch
delete_CkStringBuilder $sbReceived