I have small web/mail server with apache/mariadb. Last week we changed some of the WWW code and to make it work I changed in php.ini line :
max_input_vars to 5000 (now 4000, it was 1000 at the start)
And it seems changed something because our mariadb 10.3.28 starts making problems.
It just stops reciving any information.
Restart of mysql (and httpd) helps for 24h now ...
Log:
2022-10-05 14:28:58 2796199 [Warning] Aborted connection 2796199 to db: 'ACTIVEDB' user: 'USER' host: 'localhost' (Got an error reading communication packets)
This kind of warnings shows up sometimes but now we got dozens every hour.
In PHP i decrased max_input_vars, in my.cnf I addedd
max_allowed_packet = 124M
max_connections = 400
log_warnings = 3
Everything was at default values before.
Log level was for some time at level 4 but it stared to get too big without any time give to "crush".
Disk is nvme 500GB, Intel and shows no problems.
I would like to hear :
how to check/connect mariadb when it looks inactive
what and how (step by step) to check
Thanks all
This is not an answer, but too long for a comment.
The error "Aborted connection ... (Got an error reading communication packets)" occurs if a client disconnected without sending a COM_CLOSE notification to the server before.
This behavior is easily reproducible, e.g. by starting the command line client and killing the command line client from another session. Depending on the log_warning level, the server will write a log entry and increase the server status variable aborted_clients (or aborted_connects if this happens during connection handshake).
Here are only a few possible reasons:
Before 10.2.3 the default log_warning level was 1 (no logging of aborted_connections), since 10.2.4 default value is 2 (log aborted connections) - if the server was recently upgraded from 10.2.3 or lower the problem may have already existed in previous installation, but was not written into log file.
The PHP script(s) doesn't close the connection: As soon the script is ready with its work, make sure that all transactions were committed, memory (result sets) were freed, and the connection was closed properly.
A timeout occurred, e.g. wait_timeout was set too low and exceeded or PHP's max_execution_time exceeded (and script was killed) or net_read/write_timeouts occurred.
DNS problems: In this case enable skip-name-resolve, use IP's and verify against IP's.
Network or firewall problems
I would like to thank for sugestions and your time.
Looks like there was a problem with one table, I don't know how/why but after some time it was set up as READ-ONLY. There was no information in log about it up to level 3 (level 4 generated too much information for me :( )
The DB works some time fine (expect for one table) and in time it looks like it just hangs whole DB.
The case is still "under investigation".
About "damaged" table :
listed and read-only related thinks works fine
insert/change hangs the whole DB for 2-3 minutes and then gets back to work
after few "hangs" the DB just freezes
there was nothing strange in logs level 3
copy table to new and then change names to switch tables works (I hope so)
If anyone have any idea how to check table would be great (standard operatinos like check, analyse did nothing).
Thanks again.
I have a MySQL server that is hosting my website. Yesterday, after trying to empty a certain database, I started receiving the following error when attempting to connect to my site :
PDOException: SQLSTATE[HY000] [1040] Too many connections in lock_may_be_available()
(line 167 of /home/vksappc/public_html/prod/includes/lock.inc).
After searching online for a possible solution, I restarted the server and everything was okay. Today, however, I've noticed that the number of active connections is constantly and slowly rising until it reaches the limit of 151 :
Screenshot of thread count
At which point the server then seems to timeout those connections and everything resets, only to start its gradual climb all over again:
Screenshot of new thread count
This is really becoming a big problem and as I am quite new to managing a server, I am not too sure what could be causing this or what to do next.
Any ideas?
Turns out there was a specific connection that was stuck in a loop of sending a request unsuccessfully and trying over and over again. Once we found which connection it was, we were able to kill all its processes and fix the issue. Thanks to #WilsonHauck for the tip in the comments.
I've a MySQL 5.1.41 Server installed on a Ubuntu machine. I get connected to it through Workbench from my Windows machine over TCP/IP. I run a bigger query, after 900 seconds I got the below message, (there is no wait_timeout defined in the server's configuration file my.cnf)
Error Code: 2013. Lost connection to MySQL server during query
But when I look into the process list by using show processlist; command, I can still see my query running.
I got this link http://dev.mysql.com/doc/refman/5.0/en/gone-away.html where I found the below lines,
The problem on Windows is that in some cases MySQL does not get an
error from the OS when writing to the TCP/IP connection to the server,
but instead gets the error when trying to read the answer from the
connection.
I'm not sure whether this is the reason for my observation.
Please clarify me on this.
Thanks in advance!!
Closing connection is not a reason to stop a query. A query might be update, or kind of transaction, or select with output to remote (server) file.
Closed connection is just is just means, that you will not receive any data from DBMS after executing query (data, timings - nothing).
The reason of closing connection could be different, as SO-User posted. Try increasing
on server side:
wait_timeout
max_allowed_packet
on client side:
any kinds of timeout you find in your client (i.e. that SO-User suggests)
Do not forget to reload DBMS config and restart client (for sure)
In MySQL WorkBench we have an option to change timeout.
Find it under
Edit → Preferences → SQL Editor → DBMS connection read time out (in seconds): 600
Changed the value to 6000 or something higher.
Update
Lost connection to MySQL server
There are three likely causes for this error message.
Usually it indicates network connectivity trouble and you should check
the condition of your network if this error occurs frequently. If the
error message includes “during query,” this is probably the case you
are experiencing.
Sometimes the “during query” form happens when millions of rows are
being sent as part of one or more queries. If you know that this is
happening, you should try increasing net_read_timeout from its default
of 30 seconds to 60 seconds or longer, sufficient for the data
transfer to complete.
More rarely, it can happen when the client is attempting the initial
connection to the server. In this case, if your connect_timeout value
is set to only a few seconds, you may be able to resolve the problem
by increasing it to ten seconds, perhaps more if you have a very long
distance or slow connection. You can determine whether you are
experiencing this more uncommon cause by using SHOW GLOBAL STATUS LIKE
'Aborted_connects'. It will increase by one for each initial
connection attempt that the server aborts. You may see “reading
authorization packet” as part of the error message; if so, that also
suggests that this is the solution that you need.
If the cause is none of those just described, you may be experiencing
a problem with BLOB values that are larger than max_allowed_packet,
which can cause this error with some clients. Sometime you may see an
ER_NET_PACKET_TOO_LARGE error, and that confirms that you need to
increase max_allowed_packet.
Doc link: Error lost connection
and also check here
I'm using Node.js to run a web-server for my web application. I'm also using the node-mysql module to interface with a MySQL server for all my persistent database needs.
Whenever there is a critical error within my Node.js application that crashes my app's process I get an email sent to me. So, I keep getting this email with an error saying "Too many connections". Here's an example of the error:
Error: Too many connections
at Function.Client._packetToUserObject (/apps/x/node_modules/mysql/lib/client.js:394:11)
at Client._handlePacket (/apps/x/node_modules/mysql/lib/client.js:307:43)
at Parser.EventEmitter.emit (events.js:96:17)
at Parser.write.emitPacket (/apps/x/node_modules/mysql/lib/parser.js:71:14)
at Parser.write (/apps/x/node_modules/mysql/lib/parser.js:576:7)
at Socket.EventEmitter.emit (events.js:96:17)
at TCP.onread (net.js:396:14)
As you can see all it tells me is that the error is coming from the mysql module, but it doesn't tell me where in my application code the issue is occurring.
My application opens a db connection anytime I need to run one or more queries. I immediately close the connection after all my queries and data has been collected. So, I don't understand how I could be exceeding the 151 max_connections limit.
Unless there is a place in my code where I forgot to call db.end() to close the connection, I don't see how my app would leak like this. Even if there was such a mistake, I wouldn't get these emails sent by the dozens. Yesterday, I received almost 100 emails with roughly the same error. How could this be happening? If my application had leaked and allocated connections over time, as soon as the first error occurred the app process would crash and all connections would be lost, preventing the app to crash again. Since I received ~100 emails, this means the app crashed ~100 times, and all within a short period of time. This could only mean that somewhere in my application a lot of connections where established in a short period of time, right?
How could I avoid this problem? This is very discouraging. All help is highly appreciated. Thanks
MySQL has a default MAX_CONNECTIONS = '100' not 151 unless you changed it. Also, in truth you have MAX_CONNECTIONS + 1. The plus 1 allows a root user to logon even after you have maxed out the conenctions in order to figure out what is actually being used. When your connections are maxed out try logging on as root and running the following command from MySQL.
mysql> SHOW FULL PROCESSLIST
Post the output of this command above. Once you actually know what is consuming your resources you can go about fixing it.It could easily be your code that is leaving open connections.
You should take a look at the follwoing documentation: Show Processlist
+1 for question. Investigations showed us that node-mysql opens the connections and doesn't close them. Because of that at one moment be reach the limit of max connections. The question is why node-mysql doesn't close the connections?
Closed. This question is not reproducible or was caused by typos. It is not currently accepting answers.
This question was caused by a typo or a problem that can no longer be reproduced. While similar questions may be on-topic here, this one was resolved in a way less likely to help future readers.
Closed 6 years ago.
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I'm getting a SQL Server error:
A transport-level error has occurred
when receiving results from the
server. (provider: Shared Memory
Provider, error: 0 - The handle is
invalid.)
I'm running Sql Server 2008 SP1, Windows 2008 Standard 64 bit.
It's a .Net 4.0 web application. It happens when a request is made to the server. It's intermittent. Any idea how I can resolve it?
The database connection is closed by the database server. The connection remains valid in the connection pool of your app; as a result, when you pickup the shared connection string and try to execute it's not able to reach the database. If you are developing Visual Studio, simply close the temporary web server on your task bar.
If it happens in production, resetting your application pool for your web site should recycle the connection pool.
Try the following command on the command prompt:
netsh interface tcp set global autotuning=disabled
This turns off the auto scaling abilities of the network stack
I had the same problem. I restarted Visual Studio and that fixed the problem
Transport level errors are often linked to the connection to sql server being broken ... usually network.
Timeout Expired is usually thrown when a sql query takes too long to run.
So few options can be :
Check for the connection in VPN (if used) or any other tool
Restart IIS
Restart machine
Optimize sql queries.
For those not using IIS, I had this issue when debugging with Visual Studio 2010. I ended all of the debugger processes: WebDev.WebServer40.EXE which solved the issue.
All you need is to Stop the ASP.NET Development Server and run the project again
If you are connected to your database via Microsoft SQL Server Management, close all your connections and retry.
Had this error when connected to another Azure Database, and worked for me when closed it.
Still don't know why ..
Look at the MSDN blog which details out this error:
Removing Connections
The connection pooler removes a connection from the pool after it has
been idle for a long time, or if the pooler detects that the
connection with the server has been severed.
Note that a severed connection can be detected only after attempting
to communicate with the server. If a connection is found that is no
longer connected to the server, it is marked as invalid.
Invalid connections are removed from the connection pool only when
they are closed or reclaimed.
If a connection exists to a server that has disappeared, this
connection can be drawn from the pool even if the connection pooler
has not detected the severed connection and marked it as invalid.
This is the case because the overhead of checking that the connection
is still valid would eliminate the benefits of having a pooler by
causing another round trip to the server to occur.
When this occurs, the first attempt to use the connection will detect
that the connection has been severed, and an exception is thrown.
Basically what you are seeing is that exception in the last sentence.
A connection is taken from the connection pool, the application does
not know that the physical connection is gone, an attempt to use it is
done under the assumption that the physical connection is still there.
And you get your exception.
There are a few common reasons for this.
The server has been restarted, this will close the existing connections.
In this case, have a look at the SQL Server log, usually found at:
C:\Program Files\Microsoft SQL Server\\MSSQL\LOG
If the timestamp for startup is very recent, then we can suspect that
this is what caused the error. Try to correlate this timestamp with
the time of exception.
2009-04-16 11:32:15.62 Server Logging SQL Server messages in file
‘C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\LOG\ERRORLOG’.
Someone or something has killed the SPID that is being used.
Again, take a look in the SQL Server log. If you find a kill, try to
correlate this timestamp with the time of exception.
2009-04-16 11:34:09.57 spidXX Process ID XX was killed by
hostname xxxxx, host process ID XXXX.
There is a failover (in a mirror setup for example) again, take a look in the SQL Server log.
If there is a failover, try to correlate this timestamp with the time
of exception.
2009-04-16 11:35:12.93 spidXX The mirrored database “” is changing roles from “PRINCIPAL” to “MIRROR” due to
Failover.
Was getting this, always after about 5 minutes of operation. Investigated and found that a warning from e1iexpress always occurred before the failure. This apparently is an error having to do with certain TCP/IP adapters. But changing from WiFi to hardwired didn't affect it.
So tried Plan B and restarted Visual Studio. Then it worked fine.
On closer study I noticed that, when working correctly, the message The Thread '<No Name>' has exited with code 0 occurred at almost exactly the time the run crashed in previous attempts. Some Googling reveals that that message comes up when (among other things) the server is trimming the thread pool.
Presumably there was a bogus thread in the thread pool and every time the server attempted to "trim" it it took the app down.
You get this message when your script make SQL Service stopped for some reasons. so if you start SQL Service again perhaps your problem will be resolved.
I know this may not help everyone (who knows, maybe yes), but I had the same problem and after some time, we realized that the cause was something out of the code itself.
The computer trying to reach the server, was in another network, the connection could be established but then dropped.
The way we used to fix it, was to add a static route to the computer, allowing direct access to the server without passing thru the firewall.
route add –p YourServerNetwork mask NetworkMask Router
Sample:
route add –p 172.16.12.0 mask 255.255.255.0 192.168.11.2
I hope it helps someone, it's better to have this, at least as a clue, so if you face it, you know how to solve it.
I got the same error in Visual Studion 2012 development environment, stopped the IIS Express and rerun the application, it started working.
I had the same issue. I solved it, truncating the SQL Server LOG.
Check doing that, and then tell us, if this solution helped you.
For me the solution was totally different.
In my case I had an objectsource which required a datetimestamp parameter. Even though that ODS parameter ConvertEmptyStringToNull was true 1/1/0001 was being passed to SelectMethod. That in turn caused a sql datetime overflow exception when that datetime was passed to the sql server.
Added an additional check for datetime.year != 0001 and that solved it for me.
Weird that it would throw a transport level error and not a datetime overflow error.
Anyways..
In my case the "SQL Server" Server service stopped. When I restarted the service that enabled me to run the query and eliminate the error.
Its also a good idea to examine your query to find out why the query made this service stop
For me the answer is to upgrade the OS from 2008R2 to 2012R2, the solution of iisreset or restart apppool didn't work for me.
I also tried to turn of TCP Chimney Offload setting, but I didn't restart the server because it is a production server, which didn't work either.
We encountered this error recently between our business server and our database server.
The solution for us was to disable "IP Offloading" on the network interfaces.
Then the error went away.
One of the reason I found for this error is 'Packet Size=xxxxx' in connection string. if the value of xxxx is too large, we will see this error. Either remove this value and let SQL server handle it or keep it low, depending on the network capabilities.
It happened to me when I was trying to restore a SQL database and checked following Check Box in Options tab,
As it's a stand alone database server just closing down SSMS and reopening it solved the issue for me.
This occurs when the database is dropped and re-created some shared resources is still considering the database still exists, so when you re-run execute query to create tables in the database after it was re-created the error will not show again and Command(s) completed successfully. message will show instead of the error message Msg 233, Level 20, State 0, Line 0 A transport-level error has occurred when sending the request to the server. (provider: Shared Memory Provider, error: 0 - No process is on the other end of the pipe.).
Simply ignore this error when you are dropping and recreating databases and re-execute your DDL queries with no worries.
I faced the same issue recently, but i was not able to get answer in google.
So thought of sharing it here, so that it can help someone in future.
Error:
While executing query the query will provide few output then it will throw below error.
"Transport level error has occurred when receiving output from
server(TCP:provider,error:0- specified network name is no longer
available"
Solution:
Check the provider of that linked server
In that provider properties ,Enable "Allow inprocess" option for that particular provider to fix the issue.