Problems:
I have a web app that is getting battered. Everything is working but I get about two errors a day I can not explain. It could be the first user hitting the system because the error appears in the error log intermittently it occurred today around 7:30 am in servers time zone (same as the users).
I fixed an old issue by implicitly destroying the connection by way of the using statement as it only marks the connection as recyclable.
Error Log:
Message: 3df8d62a-6b47-479e-b5d2-b23e0db92d92 : System.InvalidOperationException: Invalid operation. The connection is closed.
at System.Data.SqlClient.SqlConnection.GetOpenConnection()
at System.Data.SqlClient.SqlConnection.get_ServerVersion()
at System.Data.Linq.SqlClient.SqlProvider.get_IsServer2005()
at System.Data.Linq.SqlClient.SqlProvider.InitializeProviderMode()
at System.Data.Linq.SqlClient.SqlProvider.System.Data.Linq.Provider.IProvider.Execute(Expression query)
at System.Data.Linq.DataQuery`1.System.Linq.IQueryProvider.Execute[S](Expression expression)
at System.Linq.Queryable.SingleOrDefault[TSource](IQueryable`1 source)
at xxxxx.Resources.Data.LINQ.DistrictService.GetDistrict(Int32 districtID)
Related Code:
//--------------------------------------------------------------------------------------------
public Domain.Data.District GetDistrict(int districtID)
{
using (_dataContext = new DistrictDataDataContext(_systemService.GetCurrentSystem().WriteOnlyDatabase.ConnectionString))
{
Mapper.CreateMap<District, Domain.Data.District>();
return (from s in _dataContext.Districts
where s.DistrictID == districtID
select Mapper.Map<District, Domain.Data.District>(s)).SingleOrDefault();
}
}
Note:
I think that this is a non-issue because the inherent behavior of the connection pooling might be firing a retry (this could just be information saying "hey we tried what you asked for but the connection was closed, we will now open one up it.") however, If this is the case, I do not get a confirmation of successful retry and I am not even sure would be expected. We have had no complaints and this cant be duplicated in house by our QA staff. I hope maybe someone else has come across this.
Related
This is a follow-up from the following question: Having trouble connecting to iSeries from .NET Core
The initial problem was resolved by setting a port number. I'm now running into the problem of the connection seemingly opening, however, hanging on the actual .Open() step - IE, never continuing on to the next line of code. For reference, here's my code block:
public static DB2Connection GetDatabaseConnection(string connectionString)
{
DB2Connection DB2Connection = new DB2Connection(connectionString);
DB2Connection.SystemNaming = true;
try
{
DB2Connection.Open();
return DB2Connection;
}
catch (Exception ex)
{
throw ex;
}
}
And my connection string is in this format: Server=###.###.###.###:#####;Database=DATABASE;UID=USER;PWD=PASSWORD;LibraryList=LIBRARY,LIST
Looking at the logs on the i Navigator, I see that there is a job name Qzhqssrv when is opened, with the user Quser, status Running, and type Prestart batch - Server. Looking into the logs for that entry, I see Job #####/QUSER/QZHQSSRV started on DATE at TIME in subsystem QUSRWRK in QSYS. Job entered system on DATE at TIME. However, it doesn't seem to continue beyond that.
Looking at the logs for a similar operation, when I'm connecting via Access Client Solutions, I get considerably more information and more steps in the logs. This leads me to believe that the system is waiting for me to send further information, however, my application is still stuck on .Open() - so perhaps there is something else I was supposed to send as part of the .Open() instruction. If so, I'm not sure what it would be.
Any insights would be greatly appreciated. Thanks!
Just to close this topic out - the problem was indeed the lack of a license. Connecting on port 446 was the correct approach, and once we got a license, we were able to get the connection working. Thanks #nfgl!
I have made a Blazor app, which is working well locally. When I put it on the server, quite often (when app uses DB context) I get this error :
Error: Connection disconnected with error 'Error: WebSocket closed with status code: 1006 ()
The user have to refresh the page, which is really annoying. You can't use app working in this way.
I have found a lot of discussions on this error, lot of plans...and almost everything is older than one year. I would expect the solution already, but haven't found anything.
Anyone knows, why is this happening and how to figure it out in the Blazor app? At least to catch this error and wait until the connection is back, so the page is not getting faded?
So far I was able to do only automatic reloading of page by javascript, when I get this error. But anyway, I can't use this solution in production, because the page is down for a second and it doesn't look good. I need to catch it before and keep the page active.
Thank you.
FYI , Have you check somewhere on the server-side like the logic that use data from DB context or the security/config in the production between IIS server and DB? If you are sure that it's come from the DB context then have you validate by test other possibility like make the test method that have long delay time/or mockup method that return the data to check whether the error still occur?
I once have a really stupid code in an object. but the code is build with no error. But it clash on runtime with no clue relate to the problem.
private string _oh;
public string oh
{
get { return _oh; }
set { oh= value; // cause infinite loop > should _oh
}
}
The worst part is that the error throwed is the same message as this question, So I quite sure there is the root clause elsewhere.
Error: Connection disconnected with error 'Error: WebSocket closed with status code: 1006 ()
I am currently trying to get search working in my Tridion 2011 installation. I read in another article that I should run the TcmReIndex.exe tool in the Tridion/bin folder to re-index all my sites. So I tried this and it failed with a message box giving the following details
Unable to get list of Publication items.
Unable to Intialize TDSE object.
The wait operation timed out
Connection Timeout Expired. The timeout period elapsed while attempting to consume the pre-login handshake acknowledgement. This could be because the pre-login handshake failed or the server was unable to respond back in time. The duration spent while attempting to connect to this server was - [Pre-Login] initialization=21054; handshake=35;
The wait operation timed out
A database error occurred while executing Stored Procedure "EDA_TRUSTEES_GETTRUSTEEETOKEN"
I have four fairly large publications (100 000+ items in total) which I am trying to index.
Any ideas?
Whenever I get "Unable to Intialize TDSE object." errors, I typically write a small test script using VBScript, and try running it on the CMS server. Whilst this does not directly solve the problem, it often gives some insight into the issue by logging information in the event viewer. Try creating a test.vbs file as follows and running it:
Set tdse = CreateObject("TDS.TDSE")
tdse.initialize()
msgbox(tdse.User.Description)
Set tdse = Nothing
If it throws any errors, please let me know, and it may help us solve the problem. If it gives you a popup with your user description, then I am completely barking up the wrong tree.
I haven't come to anything conclusive but it seems like my issue may have been a temporary one as it just started working. I did increase all timeouts in Tridion MMC > Timeout Settings by 100 times their amounts but I suspect that this wasn't the issue, when it works the connection is almost instant.
If anyone else has this issue
Restart the computer the content manager is installed on, try again.
Wait an hour or two, try again.
Increase timeouts, try again.
I've run the process a few more times and it seems to be working correctly.
After doing some refactoring to my WF4 service, I got this exception when calling some of the operations:
The execution of the InstancePersistenceCommand named {urn:schemas-microsoft-com:System.Activities.Persistence/command}LoadWorkflowByInstanceKey was interrupted by an error.
My xamlx file contains a few receive/sendreplytoreceive pairs, as shown below. The exception sometimes happens on receive2, sometimes receive3.
receive1 (no correlation, cancreateinstance=true)
send reply to receive (initializes content correlation on generated ID)
receive2 (correlates on ID, cancreateinstance=false)
send reply to receive
receive 3 (correlates on ID, cancreateinstance=false)
send reply to receive
After doing a lot of debugging and making sure all correlations where set up right, the exception disappeared for new instances of the workflow.
What does the exception mean, and why did it show up and why did it dissappear all of a sudden? Is it a code/xamlx issue or something with the infrastructure (AppFabric/SQL)?
I'm hosting the WF service with IIS/AppFabric, using AppFabric' SQL persistence.
According to this support note this error can be the result of a race condition between the Receive and a Delay activity expiring. Is this possible in your workflow.
I kinda figured mine out... aparently if you point your persistance store in a SQL previous to 2012 you get the error... so all i had to do is put mine persistance store in a SQL 2012...
When I had this problem it turned out to be a mistake in my connection string when instantiating the persistence store object.
SqlWorkflowInstanceStore store = new SqlWorkflowInstanceStore(connStr);
I realise this an old question but fixing the connection string got rid of my error while running store.Execute() so I thought I'd share!
I'm getting this error every few days. I won't see the error for a few days then I'll get a flurry of 20 or so all with in a minute or so.
I've been very thorough going throw my code so that I'm using this basic setup for my DB access.
try
{
myConnection.Open();
mySqlDataAdapter.Fill(myDataTable);
myConnection.Close();
}
Catch (Exception err)
{
if (myConnection.State != ConnectionState.Closed) myConnection.Close();
throw err;
}
The way I understand it this should execute my queries and immediately release the connection back to the pool but if something goes wrong with the query then I catch the excpetion close my connection then throw the error up, which eventually gets trapped at the application level and logs and emails me the error.
Even using this throughout my code I'm still running across the issue. What can I do to diagnose the root cause of the issue?
The issue is the number of pooled connections you can have in the pool.
In your connection string, you can add the
"Max Pool Size=100"
attribute to increase the size of your pool. However it sounds like you are concurrently running a significant number of SQL queries, all of which are long running. Perhaps you should look at ways to either shorten the queries or run them sequentially through a single connection.
changing the code to something like this makes it easier to read..
try
{
myConnection.Open();
mySqlDataAdapter.Fill(myDataTable);
}
Catch (Exception err)
{
throw err;
}
finally
{
myConnection.Close();
}
But it doesn't help your timeout..
It sound like the fill statement takes to long. Or that the problem actually is somewhere else, where you don't the connection.
SQL Profiling could help figuring out if the select statement takes to long..
A quick question here. Are you by chance on an access DB because there is a limit on the number of connections that you can concurrently have on it which would result in your type of error. SQL serve shouldn't have the same problem.
if you are runing SQL server then turn off connection pooling and see if it makes a difference to your app.
I found out with our system about 5 years ago when our company was rapidly growing that we basically broke access when we started constantly hitting the user cap. We switched to SQL in about 24 hours and haven't had a problem since.
If you're using MSSQL set up a profile running for sometime a day or two..
Make the profile to be saved to a file or a table, file is supposed to be faster...
And then having a script reading that file to a table you could easily query it to find the longest running queries.