The SSL certificate used on Quantil in China expired today.
The certificate infomation:
https://censys.io/certificates/8ae6787465ba0b7a7dc94eec50b90f9d322443cdaa547cb81ae44f17e9c81dee
Not only in China. Some clients outside of China wrongly get Quantil CNAME and went to CDNetworks (maybe affiliated with Quantil)
it seems that fastly cert will auto renew, because it's a cdn supplier hosted cert.
I am really sorry about this, it has now been fixed.
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I am really sorry about this, it has now been fixed.