An FSBucket server is currently being investigated for connection timeouts when mounting buckets. The problem has been partially identified and a first fix has been applied. Additional steps will be taken shortly to make sure everything is working as intended.
EDIT 10:49 UTC: The underlying issue has been fixed. Some applications may have had troubles mounting FSBuckets, writing or reading files stored on that server between 08:50 UTC and 10:25 UTC. Impacted applications are currently being redeployed out of caution (most of them successfully reconnected to the server after the fix has been issued).