QFX5100

I recently had an issue within the network of a customer who was experiencing a big amount of broadcast, unknown unicast and multicast – short BUM – traffic within one of his layer 2 network segments. My customer is a company which is offering dedicated servers and virtual machines to all sorts of customers and with all sorts of hardware configurations. During the last years, they did not invest much time and money into ther network which is why there are no filters for spoofed/forged traffic and loops in place by now....

Due to a software issue on one of our QFX5100 switches, we’ve decided to reinstall the software on the device via the USB reinstallation method. We tried at multiple times to boot the switch from the USB thumb drive without success, even trying multiple different USB thumb drives and different methods to write the installation image onto the switch. The result kept the same: The device showed some cryptic text on the serial interface for a few seconds and then booted once again from the JunOS image residing on the SSDs....