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Showing posts from January 27, 2013

Managing & Configuring YUM [Centos 6.0]

Yum Configuration Hi Friends, we all have faced problems while configuring yum in RedHat, Fedora and Centos. Please find the below mention steps to use all the RPM packages come along with your distribution. Yum configuration will allow you to use them with proper dependency resolution. To configure yum you must have two packages, 1. yum 2. createrepo To obtain the same do the below mention just after you have mounted you disk. There could be two conditions a.) You have the distribution disk i.e. DVD. Please follow the below mention instructions to manage the same. Your system mush have the greater or equal space of DVD. # df -ah User the partition which has the space and create a directory. In my case /mnt has the space. # mount /dev/dvdwriter /mnt # cd /mnt/Packages/ # rpm -ivh yum-* --nodeps –force # rpm -ivh vsftps* -y # rpm -ivh createrepo* --nodeps --force # cp -rpvf /mnt/* /var/ftp/pub It will create the dump on /var/ftp/pub now we need to unmount the disk. # umount /mnt b.)...

Istio multicluster, gotchas ....

istio.md Istio lets you connect, secure, control, and observe services. At a high level, Istio helps reduce the complexity of these deployments, and eases the strain on your development teams. It is a completely open source service mesh that layers transparently onto existing distributed applications. It is also a platform, including APIs that let it integrate into any logging platform, or telemetry or policy system. Istio’s diverse feature set lets you successfully, and efficiently, run a distributed microservice architecture, and provides a uniform way to secure, connect, and monitor microservices. In context of Vuclip istio allows us to reduce the code and environment configurations while keeping the similar or more feature sets at our disposal. Since istio is designed to bridge the gap for both development teams and SRE, it is essential to see and visualize that in practice. Istio will affect us in our ability to connect , secure(HTTPs TLS, mtls [Phase-2]), control(external comm...

Helm generic springboot templates

With the dramatically increasing demand for container orchestration specifically Kubernetes, demand to template K8S manifests(Json/Yaml) also came to light. To handle increasing manifests, new CRDs(Custom resource definition), etc… it became obvious that we need a package manager somewhat like yum, apt, etc… However, the nature of Kubernetes manifest is very different than what one used to have with Yum and Apt. These manifests required a lot of templates which is now supported by Helm, a tool written in GoLang with custom helm functions and pipelines. Neutral background on templating Templating has been a driver for configuration management for a long time. While it may seem trivial for users coming from Ansible, Chef, Puppet, Salt, etc…, it is not. Once one moves to Kubernetes, the very first realization is hard declarative approach that Kubernetes follows. It is difficult to make generic templating with declarative form since each application may have some unique feature and r...

Allowing users to have ssh access

Allowing users to have ssh access Hi Readers, It is one of the tasks we need to complete in order to allow users to log-in into your server without compromising your security. We are going to accomplish the following tasks, 1.) Allow the users for given domain only 2.) Must allow access to a given domain 3.) Block access for a specific domain. These questions are asked in RedHat certification examination RHCE6 We are going to complete the above mention task using iptables To give proper example we are taking 192.168.20.0/255.255.255.0 as our domain and 192.168.21.0/255.255.255.0 as other domain. Assuming that your system is a fresh installation we can remove all rules previously applied. # iptables -F The above mention command will flush all the previously applied rules. Insert a rule in your input chain by below mention command, # iptables -I INPUT -s <ip of your domain>/<subnet mask> -p <protocal tcp/udp> --dport <port> -...

Mysql Scripts in Linux Command Line Terminal

In MySQL user always tries to connect with the server via command line interface such as remote login like 'ssh' then they troubled themselves in using graphical interface and get the required output quickly. So they need to automate that task. In this Blog I am going to suggest you a way to do this ... First of all we need to know that a MySQL service is kept in /etc/init.d/mysqld and we need to invoke that in order to use mysql server and client. To do this use following command in terminal : service /etc/init.d/mysqld start or service mysqld start When mysql server is started make a directory like /home/anduril/shubham_Script and after entering into that directory use this command in your terminal. vi connect_string.sh It will create a file with the name connect_string.sh you can give any name you want. Press 'i' to edit and enter the following text : mysqlshow -u root -proot mysqladmin version -u root -proot mysqladmin variables -u root -proot mysqladmin ping -u roo...

Using Flash in your HTML

Edit your Publish settings for Flash SWFs and HTML to reflect how you want your Flash SWF to appear in your web page. Export your Flash movie as HTML. Locate your HTML file on your computer, right-click, and select "Open With". Choose either NotePad or another text editor. Copy the source code from the HTML file. Paste it into your web page's source code in the appropriate location where you want your SWF file to display. Edit the file path to reflect the location of the SWF file on your web server, and upload both your HTML and SWF file to the appropriate directories on your server. ( Note: this also applies if you're using PHP, JSP, ASP, CGI, or other web page extensions.) Your code should look something like this: <OBJECT classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,0,0" WIDTH="320" HEIGHT="240" id="You...