This problem has been recovered already.
Some client environments could not connect to Questetra during the period of between around 21 o’clock on 7th of December 2018 and around 18 o’clock on the next day [JST] due to a certificate validation error after a renewal of the server certificate. We deeply apologize to the customers for your inconvenience.

Trouble Date

  • Occurred: 2018-12-07 approximately 21:00
    • 2018-12-07 12:00 [UTC]
  • Recovered: 2018-12-08 approximately 18:00
    • 2018-12-08 9:00 [UTC] (approximately 21 hours period)

What Occurred

During the period specified above, it became unable to connect due to a certificate validation error when trying to connect to Questetra from some client environment such as Java 8u77 or earlier or Java 7u99 or earlier.

Cause of Trouble

In the periodic server certificate update work, we changed the root certificate on the certification path from DigiCert Global Root CA that uses SHA-1 to DigiCert Global Root G2 which uses SHA-256, in order to improve security. As the result, DigiCert Global Root G2 cannot be connected from a client environment that is not registered in the trust store.

Reaction

Recovery by switching back to the previous certificate (DigiCert Global Root CA)
(Please see Maintenance page for the details of the server certificate updating work.