@Badger Thank you for the suggestion! That's a good point about log4j. I used journalctl to take a peak at what's in there and while there's more, it's not particularly helpful...
The following is what was revealed by journalctl...I have pasted in two repetitions of the pattern; this pattern repeats when attempting to run Logstash with the SQS input defined in the conf file.
Nov 01 18:34:43 ip-10-0-4-244.ec2.internal systemd[1]: Started logstash.
Nov 01 18:35:16 ip-10-0-4-244.ec2.internal logstash[26318]: Sending Logstash logs to /var/log/logstash which is now configured via log4j2.properties
Nov 01 18:35:18 ip-10-0-4-244.ec2.internal logstash[26318]: [2022-11-01T18:35:18,406][INFO ][logstash.runner ] Starting Logstash {"logstash.version"=>"6.8.23"}
Nov 01 18:35:53 ip-10-0-4-244.ec2.internal systemd[1]: logstash.service: main process exited, code=killed, status=9/KILL
Nov 01 18:35:53 ip-10-0-4-244.ec2.internal systemd[1]: Unit logstash.service entered failed state.
Nov 01 18:35:53 ip-10-0-4-244.ec2.internal systemd[1]: logstash.service failed.
Nov 01 18:35:53 ip-10-0-4-244.ec2.internal systemd[1]: logstash.service holdoff time over, scheduling restart.
Nov 01 18:35:53 ip-10-0-4-244.ec2.internal systemd[1]: Stopped logstash.
Nov 01 18:35:53 ip-10-0-4-244.ec2.internal systemd[1]: Started logstash.
Nov 01 18:36:26 ip-10-0-4-244.ec2.internal logstash[27081]: Sending Logstash logs to /var/log/logstash which is now configured via log4j2.properties
Nov 01 18:36:27 ip-10-0-4-244.ec2.internal logstash[27081]: [2022-11-01T18:36:27,967][INFO ][logstash.runner ] Starting Logstash {"logstash.version"=>"6.8.23"}
Nov 01 18:37:00 ip-10-0-4-244.ec2.internal systemd[1]: logstash.service: main process exited, code=killed, status=9/KILL
Nov 01 18:37:00 ip-10-0-4-244.ec2.internal systemd[1]: Unit logstash.service entered failed state.
Nov 01 18:37:00 ip-10-0-4-244.ec2.internal systemd[1]: logstash.service failed.
Nov 01 18:37:01 ip-10-0-4-244.ec2.internal systemd[1]: logstash.service holdoff time over, scheduling restart.
Nov 01 18:37:01 ip-10-0-4-244.ec2.internal systemd[1]: Stopped logstash.
Run into this before?
Thanks!
Garrett