DevOps & Security

Install homebrew :     Run this command to install homebrew at system level $ /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"     Run bellow command and check if have any thing need to be fixed. $ sudo chown -R $(whoami) /usr/local $ brew doctor Install nginx :     Command to install nginx via brew. $ brew install nginx Install PHP 5.6 :      To install PHP v 5.6.x (script is from http://php-osx.liip.ch) $ curl -s http://php-osx.liip.ch/install.sh | bash -s 5.6  Enable new PHP 5.6 at system : $ nano ~/.bash_profile        Enter:              export PATH="/usr/local/php5/bin:/usr/local/bin:$PATH" Disable apple builtin old php-fpm version :         sudo mv /usr/sbin/php-fpm /usr/sbin/php-fpm.old Create symlink for new version of php-fpm:         sudo ln -s /usr/local/php5/sbin/php-fpm /usr/local/bin/

You had setup AWS CLI tools with AWS CodeCommit included and integrated it all to Git using the credential.helper config line. All was working correctly, then you tried to clone or push and got an error similar to: *** fatal: unable to access 'https://git-codecommit.us-east-1.amazonaws.com/v1/repos/YOUR_REPO/': The requested URL returned error: 403 *** Solution 1 : Run in terminal security delete-internet-password -l  git-codecommit.us-east-1.amazonaws.com It's is not a permanent solution, now the clock is ticking down to the next password reset done on AWS. Solution 2 : As per Amazon Docs:         1) Open the Keychain Access utility. (You can use Finder to locate it.)         2) Search for git-codecommit.us-east-1.amazonaws.com   . Highlight the row, open the context menu or right-click it, and then choose Get Info.         3) Choose the Access Control tab.         4) In Always allow access by these applications, choose git-credential-osxkeychain , and

I was checking for a nagios plugin which could filter the specified log file which i had mentioned and notify me whenever a warning or error appeared in log. Finally i get in hand check_logfile created by Gerhard Lausser. Check_logfiles is used to scan the lines of a file for regular expressions. Install the plugin on client system :  $ wget https://labs.consol.de/assets/downloads/nagios/check_logfiles-3.8.0.2.tar.gz $ tar xvzf check_logfiles-3.8.0.2.tar.gz $ cd check_logfiles-3.8.0.2/ $ ./configure $ make $ make install check_logfiles executable file will get installed on location "/usr/local/nagios/libexec" Configure Check Pattern : $ nano  /etc/nagios-plugins/config/check_log.cfg @searches = (   {     tag => 'Error',     logfile => '/var/logs/error.log',     criticalpatterns => 'Error',   } ); Here i am filtering pattern "Error" from log file which i had mentioned in logfile parameter section C

I was getting the following error in Opscenter continuously and it get resolved automatically after some time. Error initializing cluster data: The request to /APP_Live/keyspaces?ksfields=column_families%2Creplica_placement_strategy%2Cstrategy_options%2Cis_system%2Cdurable_writes%2Cskip_repair%2Cuser_types%2Cuser_functions%2Cuser_aggregates&cffields=solr_core%2Ccreate_query%2Cis_in_memory%2Ctiers timed out after 10 seconds.. If you continue to see this error message, you can workaround this timeout by setting [ui].default_api_timeout to a value larger than 10 in opscenterd.conf and restarting opscenterd. Note that this is a workaround and you should also contact DataStax Support to follow up. Solution : Workaround of this timeout is by setting [ui].default_api_timeout to a value larger than 10 in opscenterd.conf and restarting opscenterd. 

This error occurs when the node try to start and see it has snitch information which differ from previous data center. In my case, i was using DseSimpleSnitch which name the datacenter based on workload type. Previously i had enabled solr in dse default configuration file ( /etc/default/dse ) and datasenter name was Solr. Now i tried to start the dse with graph enabled, which change the name to datacenter SearchGraph which is default workload type name. CassandraDaemon.java:698 - Cannot start node if snitch's data center (Solr) differs from previous data center (SearchGraph). Please fix the snitch configuration, decommission and rebootstrap this node or use the flag -Dcassandra.ignore_dc=true Solution : 1) In the last line of  cassandra-env.sh  set in the jvm opts as given below : JVM_OPTS="$JVM_OPTS -Dcassandra.ignore_dc=true" 2) If it starts successfully, execute: nodetool repair nodetool cleanup

While changing existing cluster name in datastax, i got name mismatch exception in log file. Process i followed was changed the cluster name in cassandra.yaml configuration file. $ nano /etc/dse/cassandra/cassandra.yaml     cluster_name: 'Test Cluster1' Solution :  Change the cluster name  to "New Cluster Name" : $ cqlsh `hostname -I` cqlsh> UPDATE system.local SET cluster_name = 'New Cluster Name' where key='local'; cqlsh> exit; $ nodetool flush system Stop the cluster : $ sudo service dse stop;sudo service datastax-agent stop Edit the file : $ sudo vi /etc/dse/cassandra/cassandra.yaml     cluster_name: ' New Cluster Name ' Start the cluster : $ sudo service dse start;sudo service datastax-agent start Check Installation log :  $ cat /var/log/cassandra/output.log Reference  : https://support.datastax.com/hc/en-us/articles/205289825-Change-Cluster-Name-

                                                                  Start DSE service : sudo service dse start Stop DSE service : sudo service dse stop Configuration File Location :            /etc/dse/cassandra/cassandra.yaml            /etc/default/dse            /etc/dse/cassandra/cassandra-env.sh            /etc/dse/cassandra/cassandra-rackdc.properties ## Show information of cluster         nodetool status ## Show information about nodes and ring         nodetool ring ## Repair one or more table          nodetool repair ## Cleans up keyspaces and partition keys no longer belonging to a node.          nodetool cleanup ## Flushes one or more tables from the memtable          nodetool flush ## List files from backup data directories :         find /mnt/cassandra/data/*/*/backups/* -type f -ls ## Remove files from backup data directories :         find /mnt/cassandra/data/*/*/backups/* -type f -delete ## Retrieve the list of tokens associated w

                                                                                                                                  In production environment, network aware topology must be set. Default SimpleStrategy will not work if you want to add rack and datacenter in to an existing cluster. In production environment use NetworkTopologyStrategy. Before changing topology we must make sure inter node communication is network aware for that change the Snitch properties. Step 1) Change the snitch.             cat /etc/dse/cassandra/cassandra.yaml | grep endpoint_snitch:             endpoint_snitch: GossipingPropertyFileSnitch Step 2) After changing snitch, specify the datacenter and rack information in               properties file.                cat /etc/dse/cassandra/cassandra-rackdc.properties |grep -E 'dc=|rack='                  dc=SearchGraph             rack=rack1 Step 3) Any change in cassandra.yaml file require

                                                    Step 1 : Install Dependencies         sudo apt-get install g++ make cmake libuv-dev libssl-dev libgmp-dev  php5-dev openssl libpcre3-dev Step 2 : Install cpp-drivers as per your requirement from the link :               http://downloads.datastax.com/cpp-driver/ubuntu/         # sudo apt-get install php-config  //to solve cpp driver version issue with php         dpkg -i libuv_1.8.0-1_amd64.deb         dpkg -i libuv-dbg_1.8.0-1_amd64.deb         dpkg -i libuv-dev_1.8.0-1_amd64.deb         dpkg -i cassandra-cpp-driver_2.4.2-1_amd64.deb         dpkg -i cassandra-cpp-driver-dbg_2.4.2-1_amd64.deb         dpkg -i cassandra-cpp-driver-dev_2.4.2-1_amd64.deb Step 3 : Build Datastax C/C++ Driver.        git clone https://github.com/datastax/cpp-driver.git        mkdir cpp-driver/build        cd cpp-driver/build        cmake ..        make install Step 4 : Install the PHP extension        git clone https

                                                          Follow the steps to install OpsCenter . Don't forget to signup in   Datastax acadamey   , which we will need during the installation process  Step  1 :   Add Datastax repository file              sudo echo "deb https://login_email_Address:login_Password@debian.datastax.com/enterprise stable main" | sudo tee -a /etc/apt/sources.list.d/datastax.sources.list Step  2 :   Add the Datastax repository key              sudo curl -L https://debian.datastax.com/debian/repo_key | sudo apt-key add - Step  3 :   Install the package                      sudo apt-get update              sudo apt-get install opscenter Step 4:   Start Opscenter                       sudo service opscenterd start Step 5:   Browse Opscenter using below url               http://hostaddress:8888/ Follow the step to  Configuring OpsCenter to existing Datastax Cassandra Cluster. Step 1: