Hello ganeshfarande,
I am not sure this is the appropriate thread for your post, but since the information I plan to share can already be found in other threads, I will leave it here.
As a note, we do not write custom scripts, but can assist if you need help with a cohesive task.
While you say the script example posted works, you are taking a risk in that you have three "sends" in a row, without any intervening "waitforstrings".
Section 4.2 of the
Scripting Essentials manual available on our website states that best practice is that there should always be a
WaitForString() following each
Send() command.
The above is probably a moot point, as it sounds like you want to replace that script anyway.
Is the connection information for your 3000 routers already in an Excel spreadsheet?
If so,
see the example script in another thread, which I think will help you to accomplish your objective.