What we know about Meltdown (Intel) a...
Because there is some information noise about the two bugs and their impact, I’ve tried to make an “executive summary” about the bug itself and the potential impact of it and the workarounds which will be rolled out for Windows and Linux kernels. Sources are mentioned after quotations. Meltdown CVE-2017-5754 Information disclosure vulnerability Allows access […]
How to wipe your local docker environ...
When playing with docker on your local workstation it’s sometimes necessary to wipe the entire environment clean, but there is no single docker command which would do just that. When looking for a solution I found this useful docker script that removes everything: #!/bin/bash echo Killing all containers for i in $( docker ps -q […]
How to recover MySQL/MariaDB after In...
While InnoDB is a rather resilient storage driver, it is still possible it can get corrupted due to a disk failure or power outage. When it does happen, it’s quite possible your database will crash during startup with the following lines in the log: 170821 9:14:58 InnoDB: Assertion failure in thread 140081658566400 in file trx0purge.c […]
Debugging mobile apps on linux
Mobile apps sometimes don’t work as expected, and you need to debug what the root cause is. Can you fit the whole required set of tools on one computer? Can a single PC capture network traffic and syslog from an Android or iOS device at the same time? The answer is yes. My lab setup […]
GitLab installation on CentOS 7/RHEL ...
GitLab is a very useful open source code repository for developers. If you’ve ever used github.com, you know what GitLab is. It’s essentially your own, off-line GitHub. Technically speaking it’s a git server with a nice GUI, which will work just as well for standalone developers as for small companies. First off, install a minimal […]
Backup your entire PuTTy host list
Moving to a new PC? Setting up a new workstation? Don’t forget your PuTTy host list. Every sysadmin who has been working for a while collects a considerable number of hosts in their PuTTy configuration. Ever wondered where PuTTY saves this list? Well, it’s not in a config file you could simply copy or move. […]
Tip: Changing password through Remote...
So you need to change your password through RDP connection, but don’t know how to press Ctrl+Alt+Del on the remote system? Well, there’s a simple solution: press Ctrl+Alt+End instead. Yes, I was equally surprised.
Solaris – setting user quota on...
ZFS is a very versatile filesystem, which can hold up to 256 zettabytes of data. Yes, that’s 2^78 bytes. It is often used in enterprise solutions, because it’s just as flexible as linux LVM, but offers additional data integrity protection, and it does it so well, that it’s often recommended to use ZFS software capabilities, rather […]
PostgreSQL and MySQL Unix Time Conver...
TIMESTAMP / DATETIME to Unix Time Unix timestamp handling is a bit different in MySQL and PostgreSQL, so when you’re rewriting SQL queries to work with the other database it’s good to know how to convert Unix timestamps. PostgreSQL postgres=# SELECT EXTRACT(epoch from timestamp with time zone ‘2016-02-25 12:15:17+01’); date_part ———— 1456398917 (1 row) MySQL […]
Debugging iptables on Red Hat and Cen...
When setting up new services on a clean Red Hat or CentOS install, many administrators face problems related to the default security settings. Red Hat is secured by default, including, but not limited to, iptables firewall and SElinux, which are both enabled after installation. I will never recomend disabling iptables without trying to add required […]