This commit fixes#3252
Security patches 4.2 introduced a regression - leaf clusters ignore role mapping
and attempt to use role names coming from identity of the root cluster
whenever GetNodes method was used.
This commit reverts back the logic, however it ensures that the original
fix is preserved - traits and groups are updated on the user object.
Integration test has been extended to avoid the regression in the future.
* Session events are delivered in continuous
batches in a guaranteed order with every event
and print event ordered from session start.
* Each auth server writes to a separate folder
on disk to make sure that no two processes write
to the same file at a time.
* When retrieving sessions, auth servers fetch
and merge results recorded by each auth server.
* Migrations and compatibility modes are in place
for older clients not aware of the new format,
but compatibility mode is not NFS friendly.
* On disk migrations are launched automatically
during auth server upgrades.
This commit introduced mutual TLS authentication
for auth server API server.
Auth server multiplexes HTTP over SSH - existing
protocol and HTTP over TLS - new protocol
on the same listening socket.
Nodes and users authenticate with 2.5.0 Teleport
using TLS mutual TLS except backwards-compatibility
cases.
