My C# application is currently throwing lots of the below exceptions:
Timeout expired. The timeout period elapsed prior to completion of
the operation or the server is not responding. This failure occurred
while attempting to connect to the routing destination.
I am using linq queries and NHibernate.
I am having difficulty troubleshooting this as the exception does not occur every time the query is ran. If I take the query and run it directly on SSMS it seems to run very quickly.
The timeout exceptions only appear to occur when ran against one table in the database.
I know I am able to increase the query timeout but I would like to resolve the root cause of the issue. I have a limited knowledge in troubleshooting these issues so what are the next steps I need to take to determine what the problem is?
Increase 'Connect Timeout' of your connection string. 60 is a good number.
Timeout expired. The timeout period elapsed prior to completion of the
operation or the server is not responding.
I am getting this error in my project. Project is working fine for more than 2 years without this error. Now i am getting this error frequently.
What could be the reason for this? I have closed each and every opened connection. Is there any setting in SQL Server 2005 to avoid this issue? Or this problem is caused by network availability?
It could be due to network availability, but I had this problem some month ago.
In my case TCP/TP and share memory setting had changed in SQL Server Configuration Management.
Please check your SQL Server Configuration Management settings.
Today i have faced the same issue. So i collected all the logs.
In sql logs i got this error :
"Autogrow of file 'SSPB_log' in database 'SSPB' was cancelled by user or timed out after 30124 milliseconds. Use ALTER DATABASE to set a smaller FILEGROWTH value for this file or to explicitly set a new file size."
In my application logs I got this:
"Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding."
Does this errors related to each other??
Logging:System.Data.SqlClient.SqlException: Timeout expired. The
timeout period elapsed prior to completion of the operation or the
server is not responding.
i am a beginner when i saw in the application log files the above is the most frequent error i saw and also it is getting repeated everyday. on the database when i saw time taken for executing the particular procedure which the above function is calling is less than 5 secs.
But in the application we gave connection timeout=200s and by default command timeout=30 secs our manager says we don't have to increase the command timeout by anymore further as it is true. But still the exception is keep coming.
can anyone suggest me any solution so i can get rid of the above problem thanks
The setting in the web config, if it's the timeout in the connection string setting, is the connection timeout. It only applies to the time it takes to make a connection. From your problem description, it doesn't sound like a connection timeout is what's happening.
Command timeouts are specified in other ways. If you are using DataContext, for example, the timeout is set using the CommandTimeout property.
http://msdn.microsoft.com/en-us/library/system.data.linq.datacontext.commandtimeout.aspx
If you can give a code snippet of how you are hitting the database so we can see what classes you are using, more specific recommendations can be made.
On occasion I get the following error when trying to synchronize from SQL Express to SQL Server using Sync Framework 2.1. Once a client gets this error they have to reinitialize the scope. There can't be anything wrong with the syntax like the error states because it runs no problem for long periods of time (with inserts happening). Any thoughts?
11:18:21 AM Failed to execute the command 'BulkInsertCommand' for table 'XXX'; the transaction was rolled back. Ensure that the command syntax is correct.
11:18:21 AM Microsoft.Synchronization
11:18:21 AM at Microsoft.Synchronization.Data.ChangeHandlerBase.CheckZombieTransaction(String commandName, String table, Exception ex)
From a trace log:
WARNING, OfflineAgentMonitor.vshost, 13, 04/05/2011 11:16:17:224, Bulk command BulkUpdateCommand failed with the following exception. Rows will be retried during single apply. System.Data.SqlClient.SqlException (0x80131904): Trying to pass a table-valued parameter with 19 column(s) where the corresponding user-defined table type requires 20 column(s).
try to enable Sync Fx tracing and check if Sync Fx logs the original exception. if i remember it right, the exception is normally raised when the db connection is lost. you should be able to retry the sync though without re-provisioning the scope.
This happened to me syncing between 2 SQL Azure databases. The initial cause was that the slave DB grew larger than it's provisioned size. I increased the size, but it was a good 20 minutes before the sync stopped throwing the error
Every now and then in a high volume .NET application, you might see this exception when you try to execute a query:
System.Data.SqlClient.SqlException: A transport-level error has
occurred when sending the request to the server.
According to my research, this is something that "just happens" and not much can be done to prevent it. It does not happen as a result of a bad query, and generally cannot be duplicated. It just crops up maybe once every few days in a busy OLTP system when the TCP connection to the database goes bad for some reason.
I am forced to detect this error by parsing the exception message, and then retrying the entire operation from scratch, to include using a new connection. None of that is pretty.
Anybody have any alternate solutions?
I posted an answer on another question on another topic that might have some use here. That answer involved SMB connections, not SQL. However it was identical in that it involved a low-level transport error.
What we found was that in a heavy load situation, it was fairly easy for the remote server to time out connections at the TCP layer simply because the server was busy. Part of the reason was the defaults for how many times TCP will retransmit data on Windows weren't appropriate for our situation.
Take a look at the registry settings for tuning TCP/IP on Windows. In particular you want to look at TcpMaxDataRetransmissions and maybe TcpMaxConnectRetransmissions. These default to 5 and 2 respectively, try upping them a little bit on the client system and duplicate the load situation.
Don't go crazy! TCP doubles the timeout with each successive retransmission, so the timeout behavior for bad connections can go exponential on you if you increase these too much. As I recall upping TcpMaxDataRetransmissions to 6 or 7 solved our problem in the vast majority of cases.
This blog post by Michael Aspengren explains the error message "A transport-level error has occurred when sending the request to the server."
To answer your original question:
A more elegant way to detect this particular error, without parsing the error message, is to inspect the Number property of the SqlException.
(This actually returns the error number from the first SqlError in the Errors collection, but in your case the transport error should be the only one in the collection.)
I had the same problem albeit it was with service requests to a SQL DB.
This is what I had in my service error log:
System.Data.SqlClient.SqlException: A transport-level error has occurred when sending the request to the server. (provider: TCP Provider, error: 0 - An existing connection was forcibly closed by the remote host.)
I have a C# test suite that tests a service. The service and DB were both on external servers so I thought that might be the issue. So I deployed the service and DB locally to no avail. The issue continued. The test suite isn't even a hard pressing performance test at all, so I had no idea what was happening. The same test was failing each time, but when I disabled that test, another one would fail continuously.
I tried other methods suggested on the Internet that didn't work either:
Increase the registry values of TcpMaxDataRetransmissions and TcpMaxConnectRetransmissions.
Disable the "Shared Memory" option within SQL Server Configuration Manager under "Client Protocols" and sort TCP/IP to 1st in the list.
This might occur when you are testing scalability with a large number of client connection attempts. To resolve this issue, use the regedit.exe utility to add a new DWORD value named SynAttackProtect to the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\ with value data of 00000000.
My last resort was to use the old age saying "Try and try again". So I have nested try-catch statements to ensure that if the TCP/IP connection is lost in the lower communications protocol that it does't just give up there but tries again. This is now working for me, however it's not a very elegant solution.
use Enterprise Services with transactional components
I have seen this happen in my own environment a number of times. The client application in this case is installed on many machines. Some of those machines happen to be laptops people were leaving the application open disconnecting it and then plugging it back in and attempting to use it. This will then cause the error you have mentioned.
My first point would be to look at the network and ensure that servers aren't on DHCP and renewing IP Addresses causing this error. If that isn't the case then you have to start trawlling through your event logs looking for other network related.
Unfortunately it is as stated above a network error. The main thing you can do is just monitor the connections using a tool like netmon and work back from there.
Good Luck.
You should also check hardware connectivity to the database.
Perhaps this thread will be helpful:
http://channel9.msdn.com/forums/TechOff/234271-Conenction-forcibly-closed-SQL-2005/
I'm using reliability layer around my DB commands (abstracted away in the repository interfaece). Basically that's just code that intercepts any expected exception (DbException and also InvalidOperationException, that happens to get thrown on connectivity issues), logs it, captures statistics and retries everything again.
With that reliability layer present, the service has been able to survive stress-testing gracefully (constant dead-locks, network failures etc). Production is far less hostile than that.
PS: There is more on that here (along with a simple way to define reliability with the interception DSL)
I had the same problem. I asked my network geek friends, and all said what people have replied here: Its the connection between the computer and the database server. In my case it was my Internet Service Provider, or there router that was the problem. After a Router update, the problem went away. But do you have any other drop-outs of internet connection from you're computer or server? I had...
I experienced the transport error this morning in SSMS while connected to SQL 2008 R2 Express.
I was trying to import a CSV with \r\n. I coded my row terminator for 0x0d0x0a. When I changed it to 0x0a, the error stopped. I can change it back and forth and watch it happen/not happen.
BULK INSERT #t1 FROM 'C:\123\Import123.csv' WITH
( FIRSTROW = 1, FIELDTERMINATOR = ',', ROWTERMINATOR = '0x0d0x0a' )
I suspect I am not writing my row terminator correctly because SQL parses one character at a time right while I'm trying to pass two characters.
Anyhow, this error is 4 years old now, but it may provide a bit of information for the next user.
I just wanted to post a fix here that worked for our company on new software we've installed. We were getting the following error since day 1 on the client log file: Server was unable to process request. ---> A transport-level error has occurred when receiving results from the server. (provider: TCP Provider, error: 0 - The semaphore timeout period has expired.) ---> The semaphore timeout period has expired.
What completely fixed the problem was to set up a link aggregate (LAG) on our switch. Our Dell FX1 server has redundant fiber lines coming out of the back of it. We did not realize that the switch they're plugged into needed to have a LAG configured on those two ports. See details here: https://docs.meraki.com/display/MS/Switch+Ports#SwitchPorts-LinkAggregation