Connection limits reached.
WHAT IT MEANS
The limit on simultaneous connections was reached, and new ones are refused.
THE CAUSES
An application opening connections without closing them Several sites on one account competing A traffic spike Slow queries holding connections open longer than necessary
IMMEDIATE RELIEF
The condition frequently clears as connections time out.
If it persists, something is leaking.
THE UNDERLYING FIXES
Enable caching, so far fewer requests reach the database at all Fix slow queries, which release connections sooner Check for code opening connections in a loop
WITH SEVERAL SITES
Each holds connections. Several busy sites reach the limit collectively even when none is individually unreasonable.
CACHING IS THE MAIN ANSWER
A cached page uses no database connection. That is the difference between every visitor consuming one and almost none doing so.
WHAT TO SEND US
The time, how many applications are on the account, and whether it coincides with a traffic spike.
We can see connection counts from the server side.