In this case, Iam assuming you have verified the firewall on either side, and the network conditions are not an issue (eg. no packet loss, no crazy jitter and normal latency). In some phones such as Grandstream or on your PBX, make sure you do NOT use the "adaptive jitter buffer" or similar settings. If possible disable that or change it to "fixed". If you do, you may wonder why when you first start a call the user cannot hear you or the voice s........

Since newer versions of Ubuntu like 20, you will find there is no longer dynagen and that the dynamips provided is faulty and will segfault each time: Cisco Router Simulation Platform (version 0.2.14-amd64/Linux stable) Copyright (c) 2005-2011 Christophe Fillot. Build date: Apr 3 2018 12:20:29 Local UUID: 3c1c0b7f-2fab-4fda-b40b-74841d1bcfe0 Instance ID set to 1. netio_tap_create: unable to open TAP device tap1 (No such fi........

The issue is that Docker images are stripped down, so many tools and even python3 is missing, so you'll have to build or update the actual image yourself. I assume you have started an image with something like this and that you have the Nvidia Toolkit installed (assuming you are using GPUs). If you're not using nvidia just remove --runtime=nvidia --gpus all. docker run -it --runtime=nvidia --gpus all ubuntu bash These works for most images li........