I study both SQL and Mongodb and after a power outage at home, I can't connect to either locally. I use XE18c and SQL developer 21 for SQL and I get the silly message
An error was encountered performing the requested operation:
Listener refused the connection with the following error: ORA-12514,
TNS:listener does not currently know of service requested in connect
descriptor (CONNECTION_ID=(id)==)
Vendor code 12514
For Mongo, I can't even start the server, not even from services.
I'm on windows 10
I guess it has to do with networking....or the mercury is in retrograde or something. Any help on the former, would be great.
UPDATE
One problem fixed. Mongodb's files got corrupted from the power outage shutdown. I was able to fixe it using --REPAIR. This Mongodb doc was very useful. Recover a Standalone after an Unexpected Shutdown
One or more components are restarting or down; wait and re-try.
Related
I am hosting an Infiniband server in a linux machine and also I have created a client and connected to that service in the same machine.This works fine most of the time.
But in one instance when I was trying to connect to that server from the same client (there is no prior connectivity with that server), It is throwing RDMA_CM_EVENT_ROUTE_ERROR and the connection couldn't be established.
I don't know the root cause of this error and it is not 100% recreatable.
This made my application unreliable. I want to know the root cause of it..
We have a distributed system system built on erlang with one server node and hundreds of client nodes(the systems are distributed over the intra-net). We have a requirement that all the client nodes will connect to the server node and try to download some file(mostly the same file will be accessed by all client nodes) simultaneously by using sftp. The steps we follow for downloading the file is:
Establish ssh sftp connection between the server node and client node using function call as below:
ssh_sftp:start_channel/2 .
Then reads the file by doing function call as below:
ssh_sftp:read_file/2
The problem what we are facing is that when the number of clients are more then it is observed that few client nodes are failing to establish connection between server node. i.e. the ssh_sftp:start_channel/2 function call is failing.
Can somebody please explain me;
Is there any limitation for the number of sftp session what we can establish in a single system ?
What are the possible reason because of which the connection request fails ?
Is there anything wrong we are doing in this approach ?
Is there any better solution by which we can guarantee that all client nodes will be able to connect to server and will be able to download the file.
Observation: We tried to connect 25 client nodes to the server; during the first try only 2 nodes failed to connect and on the second try 5 nodes failed to connect. Why this random behavior ?.
I think I can answer some question below (fix me if I wrong):
Erlang is really strong when you use this concurrent, so your issue here is power of your physical hardware (server).
I don't really know what the issue in your project but my project about telecom can easy handle a thousand call which 2 process handle each call. 1 process is the master process handle the session (connection) and each other watching and handle error master process, so that be can NOT failed the connection
help me with an issue please.
My windows service depended on MS SQL server, and It has to load some information on start up, but it is starts before MS SQL and stops with an exception. I set dependency with a "sc" tool (sc config MyService depend= MSSQL) but my service still does not start on system load. MS SQL added as depednecy, I can see it in dependency tab of service properties and sc qc MyService command but my service still does not start. Can anyone help? My system is Win7, MS SQL Server 2008 R2, my service runs under local system and MS SQL is network service. Thanks a lot.
P.S. Sorry for poor English.
I think you should use dependencies
How to delay loading of specific services
or use "Automatic (Delayed Start)" option for your service Please read
WS2008: Startup Processes and Delayed Automatic Start
or
You can manage this through programming logic, that if resource is unavailable
repetitively check for it and when its available proceed for normal operation,
and you can intimate Service Client though appropriate response
Hopes that helps
I have created a Datasnap service, using Bob Swart's white paper as a guide. I have been debugging and deployed succesfully using the VCL Forms application as a server. But when I try to deploy the service version, it installs ok, I then try to start the service and it immediately stops. The error in the event log would suggest that the port set is already in use, I have tried different port numbers for both the TCPServerTransport and the HTTPService without any joy. The DSServer is not set to Autostart as I want to set the Port number from a configuration file. The error message displayed in the event log is:
Service failed on start: Could not bind socket. Address and port are already in use..
I have also tried writing to a log file on start up and execute but it looks as if it is not getting this far.
Solution needed asap, before I have to revert back to a thick client which I do not really want to do.
Thanks
Firstly get a copy of TCPView from the Sysinternals suite (now run by Microsoft) and use it to monitor which app is using the port you want to use.
I would hazard a guess that if the app works fine as a stand alone (as you say it does) and you are trying to use the same port in the service then perhaps the service app is opening up the port at startup without you realizing it and then when you try to open the port manually the app finds it already in use. Or somehow the app is trying to open the port twice. The first time is successful but, maybe due to an event or an unexpected code path, the app tries to open it a second time and fails. TCPView will help spot this.
If you are sure that the port you have configured is actually free and not in use by any other software on the machine, then there might be some anti-virus / security software running that is blocking all software from listening on either specific ports or on any port except a few configured ones. The message you are getting could be one of the symptoms of how the anti-virus / security software handles attempts by apps to start listening on a port.
We're using TFS Build Server to ensure that all files checked in by developers are going to compile to a working source tree, cuz there's nothing worse than a broken build!
Anyway we've having some problems with the drop location that Build Server wants to use, we keep getting this error:
TFS209011: Could not create drop location \build-server\drops\project\BuildNumber. No more connections can be mades to this remote computer at this time because there are already as many connections as the computer can accept
Since this is being used in a pilot program at the moment we only have 2 projects which are using the Build Server. I've checked the network share and the allowed number of connections is about 100 so I don't really get what the problem is.
Only occationally does the problem raise it's head, quite often we'll not have one for days, and then we'll have a bunch in a row.
I can't seem to find much info on this either.
I'm pretty good with TFS - but a dev not a network guy. I would GUESS that while the NETWORK SHARE itself allows 100 connections, is it possible the underlying server it is running on doesn't have some sort of limitation?
Have you checked event logs?
This problem seems specific enough I would encourage you to post to the official Microsoft forums.
It looks like the problem is to do with our install of Windows 2003, we have "Web Edition" installed and it is limited to just 10 connections.
I ended up with a post of the MSDN forums in which I got this answer: http://forums.microsoft.com/msdn/ShowPost.aspx?PostID=3967598&SiteID=1&mode=1