The Best Docker Tutorial for Beginners We quickly explain the basic Docker concepts and show you how to do the most common tasks from starting your first container, to making custom images, a Docker Swarm Cluster Tutorial, docker compose and Docker buildfiles.........

yum -y install mariadb-server systemctl start mariadb mysql_secure_installation Now we need to secure our install and set the MariaDB root password: The lines you need to act on are marked in bold shown with the answer you need. mysql_secure_installation NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB SER........

chroot which stands for change root allows you to virtually operate in another operating system even though you haven't booted it. It is commonly used to deploy new distros, applications and to fix a broken Linux/Unix install or prep a new system image without having to physically boot the drive or disk. So in this example let's say we have a drive that has a Linux OS installed on /dev/sdb1 and we have mounted this partition on /mnt/sdb1 The key point is to edit the &quo........

This is a common issue that I haven't seen many answers for on the internet. When you are using Linux as your host machine and you are connecting to another Linux machine over VNC you CANNOT use Ctrl+Alt+F1 to change virtual consoles as it sends the keys to your actual local machine. In many versions of Linux you can cycle through virtual terminals including over VNC using this: Alt + Left Arrow or Alt + Right Arrow This........

Do you hate it when your ISPhas old cached records because of a high TTLon the DNS record of the relevant domain? In plain English this means you often can't connect to a site or service because your ISP's DNS servers haven't gotten word of the new IP address (probably because they haven't checked). There are also some that are notorious for ignoring TTL and not updating records for days! But if you are lucky and smart enough to have your own Linux based DNS se........

sudo apt-get install libcurl4-openssl-dev git build-essential autotools-dev autoconf libcurl3 sudo apt-get install libcurl4-gnutls-dev git clone https://github.com/wolf9466/cpuminer-multi sudo apt-get install cmake libpthread-* libmicrohttpd-dev libssl-dev libhwloc-dev git clone https://github.com/fireice-uk/xmr-stak-cpu.git make install cd bin chmod +x xmr-stak-cpu ./xmr-stak -O xmr........

myisamchk can fix it But be careful and use the right options to avoid losing data. In fact if you haven't you should make a backup or at least manually copy /var/lib/mysql. Replace "YourDB" with the name of your database Replace "yourcrashedtable" with the name of your crashed table. The -o option is the safest and should avoid dataloss whereas -r is more aggressive and is a last option (I have lost data using -r and........

Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler! Hint do not use grub2-install! If you have trouble booting after this check this CentOS mdadm RAID booting/fixing guide. One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting The nor........

This is a VIA made VL805 USB 3.0 Chipset with 4-ports and MOLEX powered. First of all this unit was cheap at about only 9 USD with fast shipping. My biggest concern was if this was a quality unit and would it really give you full USB 3.0 speeds (some people reported with similar cards that for some weird r........

Ifigured out what caused this but don't have the solution just yet. Iwould deploy a certain script from a .tar.gz to some servers and found that /root was always owned by user and group "1000.1000". This corresonded to the user who made the .tar.gz. For some reason when extract normally with "tar -zxvf file.tar.gz" it impacts the parent directories ownership. There must be some recursion going on or possibly the .tar.gz but I haven't f........

We've all done this at some point, you work on the wrong shell window and this was my first time making this mistake but I deleted a partition table in fdisk, recreated it and saved it with "wq" and even ran partprobe! If you haven't rebooted yet then you can still recover your partition table, otherwise you're in big trouble. Fortunately since it was a live system and in use the kernel still had to use the old table like below:........

In plain English this happens after you upgrade VBOX and it rebuilds kernel modules based on a newer kernel than you are running (eg. you upgraded your kernel but haven't booted into it). It is too bad there is not a standard work around that would allow it to realize this and keep old kernel modules and use them if it detects your current kernel is older than the most recently build modules. =============== RTR3InitEx failed with rc=-1912 (rc=-1912) The........

This can be very tricky, say you are doing development on a file that is symlinked. Doing a "cp dev.file dev.file-bk" won't do what you expect, it just links back to the same file so you haven't copied or backed anything up. You need the "-H" switch to copy the actual file that is referenced by the symlink: cp -Hdev.file dev.file-bk........

Can't load ploop library: libploop.so: cannot open shared object file: No such file or directory The above happens when you haven't installed the ploop tools: yum -y install ploop........

LSi Megaraid At first it was configured as a RAID 0, then I deleted the Virtual Disk Group. I thought both drives would be shown and detected in Linux as sda and sdb but it actually shows nothing. To make them work you have to hit Ctrl+R before the system boots (when prompted) and create a Virtual Disk Group. In my case I created each one as RAID 0 (with a single drive only) as I just wanted JBOD but there is no such option or default in these Dell Pe........

I installed Ubuntu 11.04 for testing purposes but I couldn't even download SSH server: sudo sed -i -e 's/us.archive.ubuntu.com/old-releases.ubuntu.com/g' /etc/apt/sources.list After running the above make sure you do a "apt-get update" Note with the above that Ihave the search string of "us.archive.ubuntu.com" change it to whatever is in your sources.list The above does not fix all repositories either, I haven't had a chance t........

I haven't updated VBOX in ages but have never seen this issue and it has my CPU running at 100C. Manually/forcefully killing the process does not work with "kill -kill 3892". I've closed the VBOXManager and everything else related to it. This did seem to happen around the time I ran VBoxManage clonehd and it failed, the terminal issue locked up and also never wrote a byte of anything. I forced killed the VBoxManage and tried to remove &........

mysqldump: Couldn't execute 'show create table `general_log`': SHOW command denied to user 'user'@'localhost' for table 'general_log' (1142) One of my clients almost found out the hard way, here is an unlikely situation that happened. 1.) Years ago the client had another VPS to which they backed up a BLOG nightly to an .sql file, what they forgot is that the file also contained all databases (they used the --all-databases option but forgot). So imagi........

I chose this because I heard a lot of stories about scams and that many providers I contacted said they can't unlock the Canadian I717s (one said "my Bell server" is down). This method worked perfectly on my Bell I717M and should work for all I717 in Canada, I was able to insert a foreign SIMcard. This will work abroad too but remember entering CWM mode is different for I717's in other countries (at least theUS). Step 1 - Root + CWM........

I backed up everything in the /mnt/sd_card directory thinking that some dataloss could occur for some reason but purposely left my microSDHC unbacked up thinking that "it won't touch that since it's external" and Samsung's and other manufacturers website even say this (that it won't be affected and not to worry etc). Apparently I was wrong, my microSD was "undetected" and asked to be formatted after the upgrade (there goes 3-months worth of family photos). No........

For years I've always built cheap systems believing that there is little difference in more expensive components when it comes to reliability and quality, I generally believe this still except for Power Supplies. I've always bought cheap cases with nice sounding 350-550W stock/cheap/crap power supplies and haven't had any issues for the most part until recently. One such case is an NGEAR case with a 550W Optimax power supply, I always read that these supplies don't produce the........

I'm running Ubuntu 10.10 with Asus NVIDIA GT430 2.6.35-32-generic-pae #65-Ubuntu SMP Tue Jan 24 14:06:16 UTC 2012 i686 GNU/Linux Nvidia binary driver: 260.19.06 The screen sometimes completely freezes and locks up or everything starts going very slow: [1903398.100007] NVRM: os_schedule: Attempted to yield the CPU while in atomic or interrupt context [1903402.373210] NVRM: Xid (0001:00): 53, CMDre 00000000 00000080 00000000 00000005 00........

I really am a Linux fan but my comments here may not show it. Although I'm quite familiar with Linux CLI to administer servers, I find Linux GUI OS's like Ubuntu at times very clunky. This is partially because there's no such thing as a "self-made" Linux from scratch where the UIwas designed by a single team. Linux is made up of several different projects that are generally completely separate and this lack of integratiion is a key issue that makes things f........

gocr works great and it's simple, just invoke it like so: gocr filename.png The output will be printed to the screen. My only complaint/concern is that even with standard terminal output (not scanned) from a printscreen, gocr does make mistakes by inserting extra spaces where they don't belong, mistaking letters for numbers etc.. but it's definitely enough to be readable and figure out what you're looking at. I haven't tested yet with scanned input........

The normal solution would be as follows: export DISPLAY=:0.0 /usr/lib/vino/vino-server & But what happens if that doesn't work? I haven't been able to find much documentation about how to find the list of displays and how their numbering works in Xorg. Sometimes you'll get this error when trying to restart vino: Cannot open display: For some reason my display is not on 0.0........

Warning: Unable to open /dev/fd0 read-write (Read-only file system). /dev/fd0 has been opened read-only. That's a very annoying error, it's simply because Centos for some reason thinks it's wise to load the "floppy" kernel module, who has a floppy drive? I haven't seen or used a floppy for over 12 years! It's more than just annoying, if you probe the drives attached to your system, eg. with grub or partprobe, it keeps trying to locate a flopp........

[function.vB-Registry-include]: failed to open stream: No such file or directory in /www/vhosts/site.com/forums/includes/class_core.php on line 2394 This happens on a new vBulletin install where you haven't created the config.php file. Simply copy the config.php.new file into config.php and you'll be good to go.........

This really gives me a bad impression of SolusVM. I tried the "Central Backup" option and it does not warn that your server gets shutdown instantly in order to do the backup! Further, there is no way to pause or cancel the backup. Thankfully this is a test/small disk usage VPS but what if someone was running something production with a large filesize? Ihaven't used QuickBackup but hope that isn't the same thing. Everyone should be vary car........

catdoc.i386 : Decodes MS Word files into plain text or TeX format I haven't figured out how to use it, it is really not clear or obvious but it should do the job if you can figure it out. Usage: catdoc [-vu8btawxlV] [-m number] [-s charset] [-d charset] [ -f format] files........

This is based on Debian Linux but should apply equally to any *nix distro. Install LUKS/crypt-setup apt-get install cryptsetup Setup your LUKS Partition Of course change /dev/md2 with whatever partition you intend to use LUKS on. cryptsetup --verbose --verify-passphrase luksFormat /dev/md2 You'll be asked to verify your decryption password twice *DO NOT FORGET THIS PASSWORD AS IT IS NOT RECOVERABLE!........

This is a very simple solution, but most guides out there make you login twice (once to scp the key) and once to put the key in authorized_keys. There's no need for that. If you don't already have a ~/.ssh/id_rsa.pub just type "ssh-keygen -t rsa" and keep hitting enter until it's done :) Just use this code to easily enable passwordless login with SSHD key=`cat ~/.ssh/id_rsa.pub`;ssh user@192.168.5.25 "echo $key >> ~/.ssh/auth........

From the package "parted" you can use the command "partprobe" to re-read the partition table. I really hate rebooting, and that's what Iloved to hear about AHCI motherboards, that they allow hotswap so you don't have to reboot. But that's only as good as the OS, if the OS does not reload the partition table you won't be able to do anything with that new drive you attached without rebooting. Yes, even without re-reading the partiton table Linux will........

You might remember my original GluserFS/OpenVZ benchmark which produced a horrible 29.8 This is the exact same system, but using the latest 2.0.8 (with some small files patch which speeds up performance) you can see it is about 25% faster. I also haven't tuned my config files at all, but there are some settings that should increase performance on small files which I believe i........

This happened during a sync of my iPhone while installing some apps. This usually happens to non-jailbroken iPhones who are trying to install non-Apple approved software OR jailbroken phones who haven't done the "Sync update". How to fix this error and get the Sync Update Open Cydia - Manage - Sources - Edit Add this source: http://cydia.hackulo.us Then under the section "Hackulo.us" install "Ap........

Yes, Iadmit I finally got bitten by the hype as much as I can usually see through it all. Keep in mind this review is of the "stock" phone, no jailbreaking yet which is what really unleashes the customizability and whyI bought iPhone. I had better things to say about this phone before buying it, and it is a great phone, perhaps the best on the market by far, if not because of the Mac OS port onto the iPhone and all the apps, etc, etc. With that said........

I've read a lot of people complaining that their 1U servers are too loud for the office, home or whatever strange places people might want to put them. Whenever Isee the question asked, "what can be done about the noise", you'll see a myriad of silly answers like "you shouldn't have it at home or in your office at all", "1U servers are meant to be loud". These all might be valid points but they're not the solution. A good example is a........