# todo: add rollbacksSurely Facebook don't update routing systems between data centres (IIRC the situation) when they don't have people present to fix things if they go wrong? Or have an out-of-band connection (satellite, or dial-up (?), or some other alternate routing?).
I must be misunderstanding this situation here.
[Aside: I recall updating wi-fi settings on my laptop and first checking I had direct Ethernet connection working ... and that when I didn't have anything important to do (could have done a reinstall with little loss). Is that a reasonable analogy?]
Move fast and break
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<NO CARRIER>
"... We demonstrate how this design provides us with flexible control over routing and keeps the network reliable. We also describe our in-house BGP software implementation, and its testing and deployment pipelines. These allow us to treat BGP like any other software component, enabling fast incremental updates..."