DevOps Technology Stack

Problem DescriptionWe can only install software in a purely intranet (not interoperable with the public network) environment due to many restrictions in the deployment environment, so we need to download the package and install it locally on the server. The system version is CentOS 8.2, and after using the createrepo command to create the repodata, we get an Error: No available modular metadata for modular package error when installing some software, as shown below. To solve the above problem, ...

Background NotesIn the previous article Monitoring JVM with Prometheus in K8S (I), we implemented a service based on Kubernetes to monitor the JVM information of java in Pods. JVM information of the application in the Pod. However, this does not apply to all environments, because not all Pods (microservices) have their own Service in the real world, so those Pods that do not use the Service cannot monitor JVM information with the same kind of implementation as in the previous article. Now let’s ...

SSL/TLS handshake is the process of establishing a secure connection between a server and a website.SSL certificates or digital certificates have become popular because of their security for web users, website owners and publishers. They use public key cryptography to encode the transfer of data between the client and the web server. There are various types of digital certificates, but all serve the same process of providing security for both the client and the web owner. Web owners often use SS ...

Operation ScenariosThe Prometheus community has developed the JMX Exporter to export JVM monitoring metrics for use with Prometheus to capture monitoring data. Learn how to use Prometheus with JMX Exporter to monitor Java applications once your Java business has been containerized to Kubernetes in this article.   Introduction to JMX ExporterJava Management Extensions, JMX, is an extension framework for managing Java, and JMX Exporter is based on this framework for reading the runtime state ...

I. Environment Preparation1.1 Install RPM packaging, testing essential development tools$ yum install -y rpm-build rpmlint rpmdevtools 1.2 Install the dependencies required for packaging and compiling$ yum install -y gcc gcc-c++ make perl perl-WWW-Curl   II. Make the RPM package for OpenSSL Note: Remember! Do not use the root user to perform the packaging operation. This is dangerous because all binaries will be installed on the system before packaging, so you should package as a normal ...

Background of the incidentThere is a MongoDB replica set in the online environment, because it is deployed in the customer’s local server room, the customer mistakenly deleted the VMs of the other 2 nodes where the replica set is deployed (and the VMs are not recoverable). Fortunately, there is still a node alive, and after logging in to the node, we found that this node is SECONDARY, so some data may be lost, and at this time, we cannot provide read/write service to the application. At this poi ...

PrefacePercona XtraBackup(PXB for short) is a backup tool developed by Percona for MySQL database physical hot standby. It supports MySQl (Oracle), Percona Server and MariaDB, and is all open source, so it’s a real conscience. Our RDS MySQL physical backup is based on this tool. The blueprint and bug discussion of the project is on Launchpad, and the code was also on Launchpad before, but now it has been migrated to Github percona/percona-xtrabackup), the project is updated and released very fas ...

I. Installing related dependencies1.1 Installing Microsoft Sources$ curl -s -o /tmp/prod.repo https://packages.microsoft.com/config/rhel/7/prod.repo 1.2 Prevent conflicts by uninstalling the original version first (optional)$ yum remove -y unixODBC 1.3 Install the driver (all three should be installed, one cannot be missing)$ yum install -y msodbcsql mssql-tools unixODBC-devel II. Compile pdo_sqlsrv plugin2.1 Download pdo_sqlsrv extension package$ wget http://pecl.php.net/get/pdo_sqlsrv-5. ...

Project BackgroundDue to historical reasons, we have a business for data synchronization, and MongoDB is using single node in production environment. However, as the business grows, considering the importance of this synchronization business and avoiding business stoppage due to single node failure, we need to upgrade to a replica set to ensure high availability. Replica set architectureThe following architecture diagram is the MongoDB replica set high availability architecture that needs to be ...

Problem AnalysisThis is a Logstash request to ES to create a new index and the following error message appears in the Logstash log. [2021-01-11T13:23:52,381][WARN ][logstash.outputs.elasticsearch][main][08029a8bd56dc10a64b84e502acbac75f20dc2c03ac3454af5ea5a31d7aade2c] Could not index event to Elasticsearch. {:status=>400, :action=>["index", {:_id=>nil, :_index=>"catalina-prod-openapi-2021.01.11", :routing=>nil, :_type=>"_doc"}, #< ...