Restarting MariaDB Services on Swisscom Cloud - mariadb

I have some issues connecting to the db since I have reached the max_user_connections limit, it would be possibile to restart the service or to reset all the connection from web console or cli?

See KILL CONNECTION in the manual: https://dev.mysql.com/doc/refman/5.6/en/kill.html

Related

Connection timeout in AzureML 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.

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

HikariPool-1 - Failed to validate connection com.mysql.cj.jdbc.ConnectionImpl

Using azure db server but getting this error continuously in spring boot application running in a pod in Azure Kuberenetes Service. Not able to solve it.
It is happen long time inactive of database server. Restart the DB server.

DocumentDB Emulator Remote Connection

Do we have any way to connect document dB emulator from remote system ?
Can we create procedure , triggers , user defined functions etcs in document db emulator ?
The Emulator is meant for local dev scenarios, since it runs exposing a local port, you probably could (never tried, this is purely theoretical) work around the firewall and expose it, then connect from another system using your external IP and the exposed port.
There is also the local SSL certificate that you must solve (that probably is the biggest issue), though you could try with the TCP connection setting, might want to check this thread about which ports need to be opened.
Also, the Emulator does not have the entire feature set that the live service does:
The DocumentDB Emulator supports only a single fixed account and a well-known master key. Key regeneration is not possible in the DocumentDB Emulator.
The DocumentDB Emulator is not a scalable service and will not support a large number of collections.
The DocumentDB Emulator does not simulate different DocumentDB consistency levels.
The DocumentDB Emulator does not simulate multi-region replication.
The DocumentDB Emulator does not support the service quota overrides that are available in the Azure DocumentDB service (e.g. document size limits, increased partitioned collection storage).
As your copy of the DocumentDB Emulator might not be up to date with the most recent changes with the Azure DocumentDB service, please DocumentDB capacity planner to accurately estimate production throughput (RUs) needs of your application.
So, you are probably better off installing the emulator on the other system via the installer or Chocolatey and avoid all the problems.
UPDATE: My following attempted solution doesn't work. Connection Timeout, 192.168.0.101:8881 using the Node.js DocumentDB sdk. I think because of SSL. :/ Sorry. Leaving this "Answer" for documentation on what doesn't work, and if anyone knows how to bypass DocumentDB Emulator SSL.
I am trying to connect DocumentDB Emulator across my local network. (I dev on a virtual machine)
I am trying to do a port forward, to the 8081 local port that DocumentDB Emulator listens on. In Command Prompt (Run as Administrator)
netsh interface portproxy add v4tov4 listenaddress=192.168.0.101 listenport=8080 connectport=8081 connectaddress=127.0.0.1
192.168.0.101 is the network address of the PC.
Now I'm able to navigate to:
https://192.168.0.101:8080/_explorer/index.html and see the data explorer. Optimistic I can get this working for dev, with SSL turned off?
Also tried to use node.js http-proxy couldn't get it working with self-signed certificates. :(
Update, I actually got http-proxy working, but it only works if you start the servers in a specific order...
start api server
start proxy server (on windows box) with secure: true
make a failed connection
change proxy server (on windows box) to secure: false; restart;
now it's working... but useless for dev, because if you restart the API server after code change, the connection fails again.
Sample Node.js Proxy to be run on Windows box:
```
var fs = require('fs'),
httpProxy = require('http-proxy');
//
// Create the proxy server listening on port 443
//
httpProxy.createServer({
ssl: {
key: fs.readFileSync('valid-ssl-key.pem', 'utf8'),
cert: fs.readFileSync('valid-ssl-cert.pem', 'utf8')
},
target: 'https://localhost:8081',
secure: true // Depends on your needs, could be false.
}).listen(8881);
```
You just need to start the documentdb with additional parameters:
start "" "c:\Program Files\Azure Cosmos DB Emulator\CosmosDB.Emulator.exe" /AllowNetworkAccess /NoFirewall /Key=C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw==
Checkout the documentdb docker file for more details: https://github.com/Azure/azure-cosmos-db-emulator-docker/blob/master/package_scripts/startemu.cmd

AWS CodeDeploy vs Windows 2016 in ASG

I use AWS CodeDeploy to deploy builds from GitHub to EC2 instances in AutoScaling Group.
It's working fine for Windows 2012 R2 with all Deployment configurations.
But for Windows 2016 it totally fails on "OneAtTime" deploy;
During "AllAtOnce" deploy only one or two instances deployed successfully, all other fails.
In the logfile on agent this suspicious message is present:
ERROR [codedeploy-agent(1104)]: CodeDeploy Instance Agent Service: CodeDeploy Instance Agent Service: error during start or run: Errno::ETIMEDOUT
- A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. - connect(2)
All policies, roles, software, builds and other stuff are the same, I even tested this on brand new AWS account.
Does anybody faced such behaviour?
I ran into the same problem, but during my investigation, I found out that server's route table had wrong routes for 169.254.169.254 network (there was specified the gateway from the network where my template was captured), so that it couldn't read instance metadata.
From the above error it looks like the agent isn't able to talk to CodeDeploy endpoint after instance starts up. Please check if the routing tables and other proxy related settings are set up correctly. Also if you do not have it already, you can turn on the debug log by setting :verbose to true in the agent config and restart the agent. This would help debug the issue better.

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