RHEL / CentOS nmcli madness II

While writing, last weeks post became pretty awesome and should be a great, solid basis for your understanding of nmcli and network configuration in general. This week I’ll be getting more into the RHCE part of nmcli: teaming network interfaces for high availability, backup and failover and aggregation. Let’s get started.

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RHEL / CentOS nmcli madness I

RHCSA is in the bag. I took the RHEL 8 exam and passed with a whopping 283 of 300 points. Next up is RHCE 7 (version 8 is completely Ansible related which will come at a later time), which for me is a whole different ballgame. So what about this nmcli madness? Continuing my RHEL…

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ACLs: Linux advanced privileges

Another part of the RHCSA exam is some advanced privileges, mainly reading and setting Access Control Lists (ACLs). Again not too complicated, but its good to have some pointers. Probably more familiar to you are standard POSIX permissions: permissions for the owner of a file, a group and all others. But what when you need…

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Setup a NFS client on Red Hat / CentOS

So this first thing that needs a bit of work on my end, starting on my RHCSA adventure, is to setup a NFS client. It’s not too hard but there are a couple of things to consider and things like firewall and SELinux that can be easily overlooked. The RHCSA exam focuses on the NFS…

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Temporary SSH access on Linux servers

A while ago it was requested that developers should be able to login, upon request, on our production servers via SSH. Normally this is restricted to SysOps and DevOps operators. Developers have their DTA(P) to do their thing, but nevertheless management decided that they need CLI access to our live systems. Needless to say, we…

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Debian intro

My Debian intro! As I briefly pointed out in part 1 of the awesome ultimate CentOS server installation guide, I’m the happy owner of a new Linux related job. My first one since my Linux adventure started almost a year ago. A year ago I felt I had to make a decision about which distribution…

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Ultimate CentOS server setup guide 2018 – Part 2

Here we are again with part 2 of the CentOS ultimate server setup guide 2018. Following a most successful start with the basics, today we go a bit deeper with a few useful tools and must haves for your CentOS installation. There are a lot of guides out there, installing and configuring CentOS 7 and…

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Nextcloud 12 migration guide

Following one of the better decisions a couple of days ago, it was time today to re-install my webserver that runs Nextcloud. I made some errors setting it up, now almost a year ago. A couple of things could be fixed, a couple of things I’d rather not and just build it from the ground…

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New Zimbra 8.7.11 server migration guide

In the past I haven’t been so kind about the Zimbra Open Source Suite. Installing it in my own, configuring it, getting all my data to it and using it daily wasn’t a breeze. I found it especially difficult to keep it stable while ensuring security. I’ve also been somewhat active at the forums and…

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Setting up sysstat on CentOS 7.4

With my macOS background I previously always checked my server load primarily with the ‘top’ command. I still use it often to have a look at what my system is busy with at that very moment, but it’s not so useful to check what it was busy with 10 minutes ago, yesterday or at any…

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Linux random security related stuff

Security. A couple of points I came across in the last couple of weeks. Some random ramblings really, how to make your Linux server (I myself am running CentOS 7.4 server) a bit more secure. There are way more elaborate posts on this blog, but every little bit counts. Since this year I have a…

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Cleaning unneeded kernel images on CentOS 7.4

Running OpenVAS I was shocked about a couple of high security warnings. Closer inspection thought me I had an old kernel that was vulnerable against attacks. I immediately ran yum update but there was nothing to update. Huh? A uname -r and I was relieved: I was actually up to date, but looking in /boot…

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