How to Fix MySQL 'Too Many Connections' Error on Linux

How to Fix MySQL 'Too Many Connections' Error on Linux ERROR 1040 (HY000): Too many connections Your app stops working. New connections get rejected. This is one of the most common MySQL production errors. Here's exactly what causes it and how to fix it — permanently. Why It Happens MySQL has a max_connections limit (default: 151). When every connection slot is full, new connections are refused with error 1040. This happens when: Your app opens connections but doesn't close them properly (connection leak) A traffic spike creates more simultaneous connections than your limit allows Your app framework creates a new connection per request instead of using a pool Step 1: Check Current Connection Count # Connect to MySQL mysql -u root -p # Check current connections SHOW STATUS WHERE Variable_name = 'Threads_connected' ; SHOW STATUS WHERE Variable_name = 'Max_used_connections' ; SHOW VARIABLES LIKE 'max_connections' ; If Threads_connected is close to max_connections , you're at the limit. --