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  • Retrieving passwords from OCI Vault for use in Terraform

    This post is written with the intention to complement the excellent “A comprehensive guide to managing secrets in your Terraform code” by Yevgeniy Brikman. Its aim is to detail how Oracle Cloud Infrastructure Vault (OCI Vault) can be used to securely store credentials and subsequently use them in Terraform scripts. If you haven’t done so…

  • Linking Containers with Podman

    Users of the Docker engine might find that their container runtime isn’t featured prominently in Oracle Linux 8. In fact, unless you change the default confifguration a dnf search does not reveal the engine at all. For better or for worse, it appears the industry, or at least parts of it, are switching from Docker…

  • Vagrant: mapping a Virtualbox VM to a Vagrant environment

    This is a small post hopefully saving you a few minutes mapping Vagrant and VirtualBox environments. I typically have lots of Vagrant environments defined. I love Vagrant as a technology, it makes it super easy to spin up Virtual Machines (VMs) and learn about new technologies. Said Vagrant environments obviously show up as VMs in…

  • DOAG 2021 gems: DBMS_XPLAN.COMPARE_PLANS

    The most excellent #DOAG2021 conference ended last week. I have attended quite a few presentations and took lots of notes. I particularly enjoyed Conner McDonald‘s presentation about 25 years of tips and techniques. One of these tips prompted this blog post ;) Turns out I have only seen a change to DBMS_XPLAN in passing. Its…

  • Configuring a VM using Ansible via the OCI Bastion Service

    In my previous post I wrote about the creation of a Bastion Service using Terraform. As I’m incredibly lazy I prefer to configure the system pointed at by my Bastion Session with a configuration management tool. If you followed my blog for a bit you might suspect that I’ll use Ansible for that purpose. Of…

  • Create an OCI bastion service via Terraform

    Maintaining bastion hosts (a “jump box” or other network entry point directly exposed to the Internet) is somewhat frowned upon by security conscious architects, for good reasons. In my opinion the only way to connect on-premises systems to the cloud is by means of a dedicated, low-latency/high-bandwidth, and most importantly well-secured link. I never liked…

  • The performance story that didn’t turn out as one: a case of or-expansion and how the database mitigated the problem on its own

    Recently I had a bit of time to study the effect of an optimizer query transformation, the so-called or-expansion in Oracle 19c. I thought there might be performance implications with statements using bind variables transformed in this way. My limited testing suggests that isn’t necessarily the case as the optimiser is remarkably resilient. Still I…

  • Deploying I/O intensive workloads in the cloud: Oracle Automatic Storage Management (ASM)

    Over the past month I wrote a few posts about deploying I/O intensive workloads in the cloud. Using standard Linux tools, mainly Logical Volume Manager (LVM) I tried to prevent certain pitfalls from occurring. Although I’m a great fan of LVM and RAID (and their combination), there are situations where LVM/Software RAID aren’t part the…

  • Resolving slight niggles of Enterprise Manager Express 19c

    This page, should I remember I wrote it, hopefully addresses the slight niggles I have with Oracle Enterprise Manager Express. I always forget how to solve these and it takes me a minute to remember. I hope this page helps me jump start my memory. If you have any additional niggles to report please do…

  • Deploying I/O intensive workloads in the cloud: mdadm (aka Software) RAID

    The final part of my “avoiding pitfalls with Linux Logical Volume Manager” (LVM) series considers software RAID on Oracle Linux 8 as the basis for your LVM’s Physical Volume (PV). It’s still the very same VM.Standard.E4.Flex running Oracle 19.12.0 on top of Oracle Linux 8.4 with UEK6 (5.4.17-2102.203.6.el8uek.x86_64) I used for creating the earlier posts.…