Reinstalling grub on an unbootable Debian system Fixing an unbootable computer after a failed grub installation can be a bit tricky. Here’s what I ended up doing. First of all, boot the machine up and get access to the root partition: Get a Debian installation CD for the same architecture (i.e. don’t use an i386 CD if your root partition is amd64). The distro version […]

Redobackup All your documents and settings will be restored to the exact same state they were in when the last snapshot was taken. Redo Backup and Recoveryis a live CD, so it does not matter if you use Windows or Linux. You can use the same tool to backup and restore every machine. And because it […]

dj-dup-perfect-linux-backup-software With an incredibly simple user interface and the ability to encrypt and backup your data to network drives, external drives, FTP/SSH servers and even Amazon S3 storage, Déjà Dup is the perfect Linux backup solution. Set up a secure, regularly-scheduled backup in minutes. It’s like Carbonite for Linux, except you can pick where your […]

S3cmd S3 Sync How-To Program S3cmd can transfer files to and from Amazon S3 in two basic modes: Unconditional transfer — all matching files are uploaded to S3 (put operation) or downloaded back from S3 (get operation). This is similar to a standard unix cp command that also copies whatever it’s told to. Conditional transfer — only files that don’t exist at the destination in the same version […]

HA Cluster with Linux Containers based on Heartbeat, Pacemaker, DRBD and LXC,_Pacemaker,_DRBD_and_LXC The following article describes how to setup a two node HA (high availability) cluster with lightweight virtualization (Linux containers, LXC), data replication (DRBD), cluster management (Pacemaker, Heartbeat), logical volume management (LVM), and a graphical user interface (LCMC). As a result you will get a very resource- and cost-efficient shared-nothing cluster solution based completely on […]

Linux I/O Performance Tests using dd Under Linux, the dd command can be used for simple sequential I/O performance measurements. This article will provide valuable information about which parameters should be used. For more detailed I/O performance benchmarking, the Flexible I/O Tester (Fio) can be used. Basics dd can be used for simplified copying of data at the low level.[1] […]

You are here: Home >> Posts >> Database Administration >> The Accidental DBA (Day 21 of 30): Essential PerfMon counters The Accidental DBA (Day 21 of 30): Essential PerfMon counters his month the SQLskills team is presenting a series of blog posts aimed at helping Accidental/Junior DBAs ‘keep the SQL Server lights on’. It’s a little taster to let you know what we cover in our� Immersion Event for The Accidental/Junior DBA, which we present� several times each year. You can find all the […]

SQL monitor Now that you’ve got the hang of adding counters, here’s the full list we need to add, including the ones mentioned above: These are listed OBJECT first, then COUNTER Memory – Available MBytes Physical Disk – Avg. Disk sec/Read Physical Disk – Avg. Disk sec/Write Physical Disk – Disk Reads/sec Physical Disk – Disk […]

OSSEC (Wazuh) and ELK as a unified security information and event management system (SIEM). Prehistory: One of our customers was significantly impressed when he discovered AlienVault and calmed down just a little bit later after he came across their pricing. So the question “Can you, guys, find something out, so I will have more-or-less the same system but a bit lower price” was raised. Is there anything impossible […]