Is there a root cause to a cluster of certificate bugs?

[Curtis Hovey-Canonical]

We are seeing several reports of "cannot validate certificate"
problem. Are some of these bugs duplicates? Are these bugs caused by a
common issue we can fix?

generate certificates with valid time one week in past
    https://bugs.launchpad.net/juju-core/+bug/1352944
bootstrap failed, x509: cannot validate certificate
    https://bugs.launchpad.net/juju-core/+bug/1360076
Error during bootstrap: TLS handshake failed: x509: certificate signed
by unknown authority
    https://bugs.launchpad.net/juju-core/+bug/1355782
ERROR state: TLS handshake failed: x509: certificate signed by unknown authority
    https://bugs.launchpad.net/juju-core/+bug/1178312

This thread was interesting, though might be common knowledge for go developers
    https://github.com/elasticsearch/logstash-forwarder/issues/221

-- 
Curtis Hovey
Canonical Cloud Development and Operations
http://launchpad.net/~sinzui