1. Check the PostgreSQL log files for any errors or warnings that may be related to the PostgreSQL 25000 issue.

tail -f /var/log/postgresql/postgresql-9.6-main.log

2. Check the PostgreSQL configuration files for any settings that may be causing the issue.

cat /etc/postgresql/9.6/main/postgresql.conf

3. Check the PostgreSQL system tables for any issues that may be related to the PostgreSQL 25000 issue.

SELECT * FROM pg_stat_activity;

4. Check the PostgreSQL system processes for any issues that may be related to the PostgreSQL 25000 issue.

ps aux | grep postgres

5. Check the PostgreSQL system memory usage for any issues that may be related to the PostgreSQL 25000 issue.

free -m

6. Check the PostgreSQL system disk usage for any issues that may be related to the PostgreSQL 25000 issue.

df -h

7. Check the PostgreSQL system network usage for any issues that may be related to the PostgreSQL 25000 issue.

netstat -anp

8. Once the issue has been identified, take the necessary steps to fix the PostgreSQL 25000 issue.

9. After the issue has been fixed, it is recommended to use an automated database observability tool to monitor and fix the PostgreSQL 25000 in question. This tool can provide real-time insights into the performance and health of the database, as well as alerting when any issues arise. This can help to quickly identify and fix any issues that may arise in the future.