After an upgrade to 7.3.11.1, an ISG-Proxy appliance experienced a new issue - DNS stopped working.
The health checks stopped to work as well as the DRTR service
dns.x.x.x.x
Enabled Check failed DOWN
Last status: DNS lookup failed.
Successes (total): 2189 (last): Tue, 29 xxx xxxx 16:16:42 GMT (consecutive): 0
Failures (total): 17 (last): Tue, 29 xxx xxxx 16:20:48 GMT (consecutive): 9 (external): 0
Last response time: 1 ms Average response time: 0 ms
Minimum response time: 1 ms Maximum response time: 1 ms
health check failure:
xxxx-11-29 16:59:19+01:00CET "Health Monitor (WARNING): Health Check Status is 'WARNING'" 1 6F0101:1 notifier.cpp:111
DRTR:
xxxx-11-29 17:01:07+01:00CET "Dynamic categorization error: No service specified to use." 0 500000:1 cerberian_api.cpp:114
For the DNS query, see a redacted output in the snippet below.
Release : ISG: 2.4.5.1, ISG-Proxy: 7.3.11.1
Identified software defect, with ID: SG-33622
Following this identified bug, R&D has provided the fix in SGOS 7.3.12.1, and later.
Note: As always, it's recommend to first execute any upgrade in a test environment, certify that all the fixes already received in the version with the identified defect are maintained in fix version/release, before deploying in production.