That's interesting.I can't ever remember having to restart ORDS as a result
of a database outage. Even prolonged ones. We install in the PDB, not the
CDB and have one or more ORDS instances in Docker containers for each PDB.
As a result, a problem with one instance doesn't affect everything else.
Even so, these are basic connection issues you are having, so I don't think
the topology differences can be that relevant. I think this may be a job
for the ORDS team. They could certainly tell you what the expected
Do you have a non-prod/test setup where you can test some failure
scenarios? I wonder if there are specific patterns that cause the issue,
rather than a general overarching issue.
I guess in the interim I would consider a mitigation. I assume you have
multiple ORDS installations behind a load balancer to support this. If so,
you could script a restart of all ORDS instances (one at a time of course),
and call that at the end of every piece of scheduled maintenance. It would
minimise the apparent outage.
I'll see if I can get someone from the ORDS team to look at this thread.
On Tue, Oct 12, 2021 at 9:22 AM Ruan Linehan <ruandav@xxxxxxxxx> wrote:
I've researched elsewhere but not been able to identify a suitable
solution, so I'm asking here in the hopes that an ORDS aficionado might
provide some direction.
My issue is around the perception of a restart of ORDS being a requirement
to re-establishing a connection to an endpoint which may have been
unavailable for a period of time.
We run ORDS v20 on a Linux VM as part of a solution accompanying an
Exadata multitenant environment. ORDS is made available to all PDBs,
installed in the CDB. Within the 'conf' directory of ORDS - we stage all
the associated apex_aa.xml, apex_ab.xml, apex_ac.xml etc configuration
mapping files. Periodically, one of the PDB environments may be made
unavailable (i.e Closed or else RAC services stopped, or someone
inadvertently locks the ORDS_PUBLIC_USER account etc) for maintenance, for
a day or weekend etc. When this takes place, the pluggables
ORDS_PUBLIC_USER database sessions are terminated and the ORDS connection
cannot be re-established for a period of time to that PDB. So far so good.
Once the maintenance is complete, and the PDB is re-opened once again, RAC
services restarted, ORDS does not automatically re-establish a database
connection to that same PDB.
If I need to get the ORDS_PUBLIC_USER connections re-established once more
for that specific PDB, then I need to stop ORDS processes for all clients
i.e. This reads the url mapping xml and validates the associated
apex_aa.xml files etc., and eventually successfully re-establishes ALL the
database connection and all is good.
The difficulty is though, that we have literally hundreds of these PDBs in
a CDB, and literally hundreds of accompanying ORDS endpoints. So, if one of
these environments is impacted by a "maintenance" of some sort, and the
database connection is severed for a time, then it requires a full restart
of ORDS for ALL to get it back, which is rather painful.
There must be something I am missing right? I understand XML config
changes require a restart of ORDS to be picked up, but I find it troubling
that a full restart is also required when just one client endpoint
connection out of a hundred is impacted?
Is there any way I can force ORDS to 'reinit' and re-read the conf files
to re-establish a single broken connection with restarting?