Martin Bracher

Snapshots with VirtualBox and btrfs

Snapshot mechanism of VirtualBox With VirtualBox you can take snapshots of the current state (without snapshot functionality of a filesystem like btrfs) This kind of snapshot will create a kind of differential file and the original file will(…)

Oracle LDAP Timeouts

Introduction, Setup You are using 2 or more LDAP servers for Oracle name resolution to be highly available? Do you kown what happens if an ldap server is down or not reachable? You probably expect that it tries the(…)

Setup an LDAP server for Oracle naming on Enterprise Linux 9

Introduction To centralise Oracle naming resolution, you can use an LDAP server. You can use the commercial products from Oracle like Oracle Internet Directory (OID) or Oracle Universal Directory (OUD). Alternatively, you can also use OpenLDAP from your Linux(…)

TNS_ADMIN – which *.ora files Oracle will use

Introduction Oracle uses some configuration files (*.ora) related to the network. tnsnames.ora: A mapping of an alias name to a connect string for Oracle. A kind of “/etc/hosts” for Oracle databases ldap.ora: Configuration of ldap servers to use. A(…)

Administer Oracle Database Appliance (ODA) with odacli and Ansible

Introduction To administer an Oracle Database Appliance (ODA), you probably use the odacli commandline tool. The principle of this tool is to run jobs in background. Fire-and-forget… or Fire-and-poll odacli update-repository -f "/tmp/odacli-dcs-19.30.0.0.0-260210-GI-19.30.0.0.zip" This command returns(…)

Remove grant to public in Oracle databases

CIS recommendations The Center for Internet Security publishes the “CIS Oracle database 19c Benchmark” with recommendations to enhance the security of Oracle databases. One type of recommendations is to remove grant execute to public (chapter 5.1.1.1-5.1.1.7 Public(…)

Shell and Perl in one script

To run a Perl script directly like a binary from within the shell, you have to set the executable flag on the script Add the shebang line (the 1st line (#!...) specifiyng the interpreter to use) #!/usr/bin/env perl(…)

Errorhandling in Ansible

Errors in tasks – abort or ignore? Per default, if a task in a playbook fails, then the execution of the playbook is stopped for that host. - name: PLAY1 hosts: localhost gather_facts: no tasks: - name: let(…)

Parallel execution of Ansible roles

Introduction You can run a playbook for specific host(s), a group of hosts, or “all” (all hosts of the inventory). Ansible will then run the tasks in parallel on the specified hosts. To avoid an overload, the(…)

Ansible: reduce output in loops – or replace loops

Reduce the output If you do a loop in Ansible, it always prints the item variable for each loop. “item” is the current list element. If you are looping over a list with small values, then the output(…)