Connection timeout in AzureML studio - azure-machine-learning-studio

I'm trying to connect a VM I have in AzureML studio. I keep getting the following: Connection attempt timed out for ''. Verify that server is accessible and SSH service is accepting connections.

Go to your VM config and test your connection through the 'connect' tab. Is your test successful? If not, check if port 22 is blocked. Watch for automated blocking rules applied to your VM.
we have DSVM attach in preview - might be interesting for you: https://github.com/Azure/azureml-previews/tree/main/previews/dsvm-attach.

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corda CENM networkmap server start failing to connect database after a few week run

we operate CENM(1.2 and use helm template to run on k8s cluster) to construct our own private network and keep on running CENM network map server for a few week, then launching new node start failing.
with further investigation, its appeared that request timeout for http://nmap:10000/network-map causes problem.
in nmap server’s log, we found following output when access to above url with curl.
[NMServer] - Error while handling socket client message com.r3.enm.servicesapi.networkmap.handlers.LatestUnsignedNetworkParametersRetrievalMessage#760c53ea: HikariPool-1 - Connection is not available, request timed out after 30000ms.
netstat shows there is at least 3 establish connection to the database from the container which network map server runs, also I can connect database directly with using CLI.
so I don’t think it is neither database saturated nor network configuration problem.
anyone have an idea why this happens? I think restart probably solve the problem, but want to know the root cause...
regards,
Please test the following options.
Since it is the HikariCP (connection pool) component that is throwing the error it would be worth seeing if increasing the pool size in the network map configuration may help - see below)
Corda uses Hikari Pool for creating the connection pool. To configure the connection pool any custom properties can be set in the dataSourceProperties section.
dataSourceProperties = {
dataSourceClassName = "org.postgresql.ds.PGSimpleDataSource"
...
maximumPoolSize = 10
connectionTimeout = 50000
}
Has a healthcheck been conducted to verify there are sufficient resources on that postgres database i.e basic diagnostic checks ?
Another option to get more information logged from the network map service is to run with TRACE logging also:
From https://docs.corda.net/docs/cenm/1.2/troubleshooting-common-issues.html
Enabling debug/trace logging
Each service can be configured to run with a deeper log level via command line flags passed at startup:
java -DdefaultLogLevel=TRACE -DconsoleLogLevel=TRACE -jar <enm-service-jar>.jar --config-fi

AS/400 DDM service not running

I wanted to make a ODBC connection from Windows PC to AS/400 DB2 server and I wrote a VBA program. But I got the following error.
Remote port could not be resolved
Then, I checked the status of server with CWSPING and got the result below:
I - Verifying connection to system 192.168.1.2...
I - Successfully connected to server application: Central Client
I - Successfully connected to server application: Network File
I - Successfully connected to server application: Network Print
I - Successfully connected to server application: Data Access
I - Successfully connected to server application: Data Queues
I - Successfully connected to server application: Remote Command
I - Successfully connected to server application: Security
E - CWBCO1011 - Remote port could not be resolved
E - CWBCO1008 - Unable to connect to server application DDM, returned 8407
I - Successfully connected to server application: Telnet
W - CWBCO1015 - Connection verified to system 192.168.1.2, but there were warnings
This means DDM service is not working on the server. ODBC connection requires DRDA, which runs upon DDM service, so I think running DDM service is the key to make ODBC connection. So I tried STRTCPSVR *DDM command but got the result below
*DDM not valid for parameter SERVER
And also tried CHGDDMTCPA AUTOSTART(*YES) PWDRQD(*YES) command, but got an error and I got stuck.
Command CHGDDMTCPA in library *LIBL not found
Does anyone have an idea of enabling DDM server on AS400?
Server: IBM AS400
OS version: V4R1
Try STRHOSTSVR *DATABASE.
STRHOSTSVR is used to start servers associated with IBM i Access and i Access Client Solutions.
STRTCPSVR is used, in general, to start servers associated with TCP/IP like FTP, Telnet, etc. Except the HTTP Server which is started via the Web Administration site at http://<server>:2001.
Additionally to the answer from #jmarkmurphy:
You can easily check netstat *cnn for open ports.
There is actually a tcpsvr named *ddm but that isn't used with ODBC.
ODBC-Access only needs host server *database. There aren't any further requirements for host servers.
For checking which services are started at tcp startup time, use strfdu, option 5 with the file qusrsys/qatocstart. From there you can easily view and change what should be started and what not.
Finally, I got connected by using JDBC. The summary of what I found is as follows:
ODBC seems using DRDA(port 446) but the server does not have DRDA/DDM service
OLEDB seems connecting Data Access(port 8471) but issued unknown error
JDBC also connection Data Access(port 8471) and it worked!
The first error I encountered when using ODBC is "Remote port could not be resolved". What happened behind this seems as follows:
ODBC asked Server Mapper(port 449) to find DRDA port(it may change on a server)
Server Mapper could not find DRDA port because the server has no DRDA service
ODBC showed "port not resolved" error
Then, I tried OLEDB this time. It checked user/password correctly but issued unknown error. When I put incorrect password, it showed "password is incorrect", which means OLEDB successfully log on to the server but got some error after sign on.
The last, I used JDBC and successfully connected! Generally, the connection url is like "jdbc:as400://" but it showed error. Using trace of JDBC, it seems to have problem on sign on to the server. So I changed the url to "jdbc:as400://:8471", then I finally connected. Looking into trace, it directly access to port 8741 and send user/password and get connected. I don't know the detail, but it worked!
Appreciated for your help!

SSH Listener not closing

I'm trying to write a go application that would allow me to perform reverse ssh tunneling between a Windows machine and a Linux machine using the go ssh library.
In the process of doing so, I create a listener on the remote machine, as follows:
remoteListener, err := sshClient.Listen("tcp", remoteString)
where sshClient is an object of type ssh.Client and is configured to connect to the remote machine.
The issue here is that when the sshd process on the Linux machine disrupts the connection with the application, the ssh Listener remains alive on the remote machine. So, reconnecting with the application fails because a listener is already running on the same port on the remote machine.
How do I get around this issue? Does the ssh library allow me to define a timeout on the listener?
I'm just waiting for the timeout after reconnecting. I found no other easy solution for this.

SocketException: No connection could be made because the target machine actively refused it XX.XXX.XX.XXX:443

I got 2 servers with two equal wcf services hosted on them and one client application server. I can connect to endpoints and send a requests to both services using test wcf client app (.NET Web Service Studio) from my local machine successfully. But when I am trying to connect from client application server using the same test wcf client app I successfully connected only to the one wcf service server, but I have got an error when connecting to another one:
System.Net.WebException: There was an error downloading 'https://XXX/XXX?wsdl'. ---> System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: No connection could be made because the target machine actively refused it XX.XXX.XX.XXX:443
I performed netstat -an | find "443" command in command prompt on the client server and on my local machine to find out the difference and here what I have got:
1. On my local machine:
2. On the client app server:
What I already tried to do on client application server is:
- turned off firewall;
- stopped windows firewall service
- uninstalled mcafee virusscan enterprise application.
(I tried to set "prevent mass mailing worms from send mail" first, but mcafee was in foreign language that I don't understand, so I just uninstalled it)
after running command netstat -aon | findstr "443" on client application server I have got this result:
but I still got an error.
Does anybody know how to solve this issue?
Could be the problem on the wcf service server side?
The solution was predictable simple one - firewall was blocking the port,
but it's important to notice that the issue was caused by firewall on the wcf service server side, but not on client application server, which is making the request to that service.
I asked the technical support of that server, and they made firewall changes.
After that error was disappeared.
I faced the same issue and tried different ways to fix this. Nothing works. Later i found the issue which is, the application i tried to run is https and in my IIS, https binding was not created. I created binding https with the website and it works.

Getting a sql connection error when trying to login

I have a login page that works in my local development environment. When I push the site onto the web server, i am getting this error when trying to login from the asp.net login control.
An error has occurred while establishing a connection to the server. When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)
I cannot figure out why it does not work on the server. Do I need to add anything or change something in the web.config?
This support article may help. It may also be a firewall issue or an authentication issue on the new setup (but the error message makes that less likely).
For resolving error 26 in sql server you need to do the following steps.
At Server System
1. Under surface area configuration manager-Open up remote connections.
2. Add into firewall 1433 and 1434 port no as n exception.
3. Open port 1433 on router for WAN access.
4. Add client machine ip address as an exception to your antivirus or allow LAN settings in antivirus.
5. Now try to check if both client and server are connected to each other.
for this type "ping IP address of remote system" at run and if reply is obtained then do same for server machine.
If reply is obtained from both machines.
Open Sql server and try to connect to remote machine which allow remote connections using its ip address. U will surely get connected to server machine
See this video
Check to make sure TCP/IP is enabled on the SQL Server. For whatever reason, named pipes and TCP/IP is off by default. Also make sure you are trying to connect to the correct instance (maybe you are using ./SQLEXPRESS locally and on the server SQL is installed on the default instance). Lastly, make sure the database you are trying to connect to exists on the server.

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