I think that was from an outage in 2010:
https://engineering.fb.com/2010/09/23/uncategorized/more-details-on-today-s-outage/



On Mon, Oct 4, 2021 at 6:19 PM Jay Hennigan <jay@west.net> wrote:
On 10/4/21 17:58, jcurran@istaff.org wrote:
> Fairly abstract - Facebook Engineering -
> https://m.facebook.com/nt/screen/?params=%7B%22note_id%22%3A10158791436142200%7D&path=%2Fnotes%2Fnote%2F&_rdr
> <https://m.facebook.com/nt/screen/?params={"note_id":10158791436142200}&path=/notes/note/&_rdr>

I believe that the above link refers to a previous outage. The duration
of the outage doesn't match today's, the technical explanation doesn't
align very well, and many of the comments reference earlier dates.

> Also, Cloudflare’s take on the outage -
> https://blog.cloudflare.com/october-2021-facebook-outage/
> <https://blog.cloudflare.com/october-2021-facebook-outage/>

This appears to indeed reference today's event.

--
Jay Hennigan - jay@west.net
Network Engineering - CCIE #7880
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