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New Member

Packet Tracer 6.0.1 - Buffer Full



I'm experiencing an issue with Packet Tracer 6.0.1. When I try to send any packet over my network I recieve a "Buffer Full" error after so many hops. It gives me the option to clear the buffer but once I do the packet simulation resets. Because of this it's impossible to tell if my network is flawless, because it's impossible to simulate a packet on through the entire journey.

Does anyone have a solution to this "Full Buffer" issue?

New Member

Hello, I'm Sofyan from


Sorry to see that even after three years, this issue is still trending first in search engines without any single answer, and even in the newest version of (PacketTracer v7 atm), people are still facing this problem due to ambiguity.

I'd post here to answer any future similar questions.

So, the problem is actually not even a problem, rather than a misunderstanding of how the protocol filters work in PacketTracer's simulation mode. If you go back and enable all the protocols to be visible in the workspace by toggling the (show all/None) button in the simulation mode, you'd find a plenty of messages, most of which are STP messages, and you'd discover that your event list has really been saturated.

Toggling the filters doesn't stop the program from capturing the events, and apparently, the events are captured faster, and you can barely use one ICMP message without getting ( Event buffer full ) error.

To workaround that, head to (Options) in the main menu of your program and select (Preferences).

Once the preferences window appears, go to (Miscellaneous) tab and optimize the following options to meet your needs:

Simulation - Buffer full action:

- Prompt : means that the event buffer error message appears.

- Auto clear EventList: means the previous events in the list will be cleared and you continue with the current running ones.

- Auto view previous events: means that you pause the simulation at the current moment.

You should choose the first option if you can't decide, or just leave it because that's the default.

The second option however, is going to solve your problem:

Simulation- Buffer behavior:

- Buffer filtered events only

You must tick this option to activate it if you only care about the filtered types of messages, and the error will eventually disappear.

Only the messages you are interested in, will be captured and saved to the event buffer or list.

I hope this solves the problem for the future.

New Member

Thank you!

Thank you!

I've had this problem since 2012. Although I haven't been looking for an answer until today, i just basically ignored it.

Thank you

Thank you