Some time ago we discovered that certain very slow downloads were getting abruptly terminated and began investigating whether that was a client (i.e. web browser) or server (i.e. us) problem.
Some users were unable to download a binary file a few megabytes in length. The story was simple—the download connection was abruptly terminated even though the file was in the process of being downloaded. After a brief investigation we confirmed the problem: somewhere in our stack there was a bug.
Describing the problem was simple, reproducing the problem was easy with a single curl
command, but fixing it took surprising amount of effort.
CC BY 2.0 image by jojo nicdao
In this article I'll describe the symptoms we saw, how we reproduced it and how we fixed it. Hopefully, by sharing our experiences we will save others from the tedious debugging we went through.
Two things caught our attention in the bug report. First, only users on mobile phones were experiencing the problem. Second, the asset causing issues—a binary file—was pretty large, at around 30MB.
After a fruitful session with tcpdump
one of our engineers was able to prepare a test case that reproduced the Continue reading
Check out these wireless vendors driving innovation in enterprise WiFi.
IT organizations can manage the hybrid IT challenge by focusing on monitoring.
China's e-commerce giant joins OpenDaylight to share its SDN experience.
SmartSky wants to avoid hardware as much as possible.
After I told you that I’m not going to Interop, I got numerous emails along the lines of “but I was really looking forward to attending your workshop” so I started looking for a solution that would combine the best of online and classroom worlds.
Here’s my first attempt: an interactive online course combining topics from two of my Interop workshops. I’m still working on the detailed agenda and plan to have it ready around May 1st. In the meantime, I’d really appreciate your feedback – leave a comment or send me an email.
Cisco Live takes place in Las Vegas between the 10th and 14th of July this year. Every Live event, Cisco holds a customer appreciation event (CAE) in an arena close by the conference center. Last year we saw an amazing performance from Aerosmith hosted in San Diego. The year before that, Imagine Dragons put on a show in San Francisco.
This years event will be hosted at the T-Mobile Arena on the Las Vegas strip. This is a very new arena that opened on April, 6, just days ago. The pictures below show renderings of the arena.
T-Mobile Arena® will be the destination in Las Vegas for live events – from amazing music acts to thrilling sporting events – it will set a new standard for what entertainment means in the city that does it best. The 20,000-seat T-Mobile Arena ® will host exciting, world-class events with something for everyone – from UFC, boxing, hockey, basketball and professional bull riding to high-profile awards shows and top-name concerts.
Cisco is not only holding their CAE there. The arena also uses Cisco technology called Cisco StadiumVision which is an innovative digital content distribution system. The system is used to centrally manage and Continue reading