[root@rhce-ryanrudolf]# rm -rf / 2> /dev/null

things I break/fix for fun and learning

Jun 1, 2018 - 2 minute read - Comments

Modifying Bootloader of WDR3600

I recently acquired a TP LINK WDR3600. It’s a dual band router with gigabit ethernet ports and 2 USB ports. It is also fully supported by OpenWRT / LEDE, which is one of my favorite open source projects. I want to modify the bootloader (u-boot) because I need a quick and easy way to recover from bricks without using special tools. One of the benefits of using a modified bootloader is an embedded web server that can be used to (re)flash the firmware. I want to build and customize my own firmware for this router, and even though I have done this before without bricking, having a failsafe method gives more peace of mind.

May 11, 2018 - 2 minute read - Comments

Additional Storage when / (root) Partition is Full

A question was raised in one of the facebook groups I frequent in that caught my attention. The question goes like this - “I have centos 7 vm and it looks like I’ve run out of space on my main partition (/dev/mapper/centos-root). Since it is a vmware vm, i can increase that drive but how would configure in linux to see the added storage?”

This has not happened to me before, and I am curious on how to solve this particular problem in case I have to deal with it. I tried to simulate this on my test VM. First thing I did is reconfigured the VM to use additional 1GB HDD. And then the rest is purely command line magic!

May 5, 2018 - 4 minute read - Comments

Deploying vCenter 6.7 appliance

My current homelab environment revolves around vSphere 6.5. I am using ESXi 6.5 as the hypervisor and vCenter 6.5 for centralized management. Recently vSphere 6.7 was released and it is available as free download for 60days evaluation. I am going to try to migrate my homelab from 6.5 to 6.7 and the first thing I will do is the vCenter.

May 4, 2018 - 2 minute read - Comments

Upgrading from vSphere6.5 to vSphere6.7

It’s going to be a busy weekend for me! I am using an evaluation version of vSphere 6.5 for quite a while now. Recently they released vSphere 6.7 but it was not available for evaluation - until now! In preparation for this, I have started to download all the needed packages so that in the weekend all I need to do is install them. One thing got my attention - vCenter Server Appliance is available for download to be evaluated! In the past this is not available, only vCenter Server for Windows is available. This will be one of the things I will focus and test on - standalone vCenter Server appliance or Vcenter Server that needs Windows. (Even without testing, I’m already leaning on using the appliance version as it is based on Linux, and less Windows license to worry about.)

May 4, 2018 - 2 minute read - Comments

Fedora27 to Fedora28 Upgrade Successful

Little bit background about Fedora : Fedora is a Linux distribution developed by the community-supported Fedora project and sponsored by RedHat. Fedora is the upstream version with all the new bells and whistles and serves as a testbed / playground for all the new features that will be added soon to the downstream version which is RHEL / CentOS. Fedora and RHEL / CentOS are on the same ecosystem - the new features of Fedora today will soon be the new features of RHEL / CentOS someday.

Apr 19, 2018 - 2 minute read - Comments - linux

Adblocking at the DNS Level

I have 2 wonderful kids who are at the age of curiosity and exploration with access to Internet using their own tablets (for school reading / games / research) and soon with a laptop / desktop. I need to protect them from the darkside of the Internet – gambling, fake news, porn, malware, inappropriate advertisements, etc etc.

One solution is to use adblocker on each endpoint device that connects to the Internet. This is OK, but has several downsides. Mainly this needs admin rights for it to work properly (root access on tablets / phones which I don’t have). Another downside is you have to configure this on each endpoint device, which can be overwhelming and time consuming.

Apr 16, 2018 - 1 minute read - Comments

Bottleneck in my HomeLab

I recently rebuilt my plex media server inside a VM. I was transferring several media files and noticed that the throughput peaks at 10MB/s and averages to about 7.6MB/s.

The source computer is older and only have 10/100Mb/s network interface while the destination computer is my ESXi server that has a 1Gb/s network interface. Both are connected by D-LINK DIR-615 which also maxes at 100Mb/s.

Apr 15, 2018 - 4 minute read - Comments

NIC Bonding / Teaming in RHEL7

NIC bonding / teaming allows for redundancy and resiliency in server systems. If one of the NIC (network interface card) fails, the server still have network connectivity.

Configuring this in RHEL is pretty straightforward. There are several ways to configure this, and I am familiar doing this in the command line using nmcli.