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• How do I disable Greylisting in SmarterMail?
  To disable greylisting (graylisting) you will need to login as an admin and follow these simple steps.   Expand “Domains” and click on “All Domains” and find ...
• How do I convert text in a file to lower case?
  Converting the content of a file to lowercase a simple process using ‘tr’ cat input.txt | tr ‘[:upper:]‘ ‘[:lower:]‘ > output.txt Remember the input.txt and output.txt can ...
• How do I pair a Current Cost transmitter with an Envi/CC128 Monitor
  Follow this procedure to pair the Transmitter (standard or mini) on an appliance channel. Press the “Up” or “Down” buttons until you find the Appliance channel ...
• How do I find all sites hosted on the same IP address?
  To find all sites hosted on the same IP address is not an easy task due to the way a server can be configured to ...
• How do I recalculate Plesk statistics for a site?
  If for some reason Plesk does not update the statistics properly for a site or you wish to re-run them after changing log files etc ...
• How do I fix Unable to connect to database: saved admin password is incorrect (Plesk)?
  ERROR: PleskFatalExceptionUnable to connect to database: saved admin password is incorrect. 0: /usr/local/psa/admin/plib/common_func.php3:190psaerror(string ‘Unable to connect to database: saved admin password isincorrect.’)1: /usr/local/psa/admin/auto_prepend/auth.php3:93 The following instructions assume ...
• How do I graphing mysql statistics in Cacti?
  Graphing mysql statistics in Cacti The HOWTO below will guide you through creating statistics graphs for MySQL usage in Cacti.   We have modified the authentication to use ...
• How do I factory reset a Siemens Gigaset A580IP / C475IP / S685IP
  To remove all settings from the phone (It will revert back to DHCP and a default pin of 0000).   Remove the cables from the base station. Put ...
• How do I upgrade the firmware on a Cisco/Sipura SPA942/SPA962/etc using TFTP?
  You will need a TFP server to update the firmware. Obtain the latest firmware for your device from Cisco Support. Extract the archive and copy the *.bin ...
• How do I set the time on the Current Cost Envi?
  Press and hold the "OK" button until the red light below flashes. Using the up and down arrows set the hours (using the 24 hour clock). Press ...
• How do I resolve the Error: "please wait for graphics to be generated" on HSphere/SiteStudio?
  This normally occurs when imaker has stopped running, you can check its current status by using   /hsphere/shared/SiteStudio/imaker.sh status   If this shows the process is not running then ...
• How do I test SMTP Auth using telnet?
  To test AUTH LOGIN Prepare the username and password by encoding them as follows:   $ perl -MMIME::Base64 -e 'print encode_base64("user\@domain");'dXNlckBkb21haW4=  $ perl -MMIME::Base64 -e 'print encode_base64("password");' cGFzc3dvcmQ=   Please make sure ...
• How do I disable Aero snap?
  To disable Aero snap (Dragging windows off the edge get arranged into half of the screen): Click on Start->Control Panel Select the "Ease of Access center" category Select ...
• How do I install Softaculous on cPanel?
  To install Sofaculous follow these simple instructions: Login via SSH to the server (as root, or "su - root" if accessing via another user. Execute the following ...
• How do I clear a saved password for a network share?
  To clear a saved password for a network share to allow you to use a new username/password use:   net use \\<sharename> /delete /yes   Replacing the <sharename> with ...
• How do I block inbound mail to a Linux server?
  To temporarily block inbound mail to a mail server by  blocking access to port 25 on the server use the following iptables command (this allows ...
• How do I get a list of all databases on pgsql/PostgreSQL?
  To get a list of all databases on PostgreSQL su to the postgres user:   su - postgres   Once you have switched to the postgres user simply issue ...
• How do I backup a pgsql/PostgreSQL database?
  To get a list of all databases on PostgreSQL su to the postgres user:   su - postgres   Once you have switched to the postgres user simply issue ...
• How do I activate Windows (w2k8/web/etc) using a MAK from the command line?
  To change the licence key and activate Windows: Login to the server and run an Administrator command prompt. Type the following replacing the text with your MAK key ...
• How do I open a new window in Google Chrome?
  Press Ctrl-N to open the new window. ...
• How do I open a new tab in Google Chrome?
  Press Ctrl-T ...
• How do I open a link in a new (background) tab in Google Chrome?
  Using the mouse hold Ctrl key then press the left (primary) mouse button, or press the middle mouse button. ...
• How do I open a link in a new (active) tab in Google Chrome?
  Hold down Ctrl+Shift then press the left (primary) mouse button. ...
• How do I open a link in a new window in Google Chrome?
  Hold down Shift and then press the left (primary) mouse button. ...
• How do I close the active tab in Google Chrome?
  Press Ctrl-W ...
• How to I switch between browser tabs in Google Chrome?
  You can use Ctrl-PgUp and Ctrl-PgDn to move forwards and backwards in the tabs. Alternatively you can move directly to any of the first 8 tabs ...
• How do I update the Plesk limits when the user is over disk quota?
  Normally the Plesk control panel will not allow you to update the limits of a hosting account if the account is over quota. This can ...
• How do I view the expiry date of an SSL certificate?
  To view the expiry dates of an SSL certificate simply run openssl x509 -noout -in <filename> -dates Which will output data in a format similar to this notBefore=Jan ...
• How do I convert a .asf file to .wav?
  Using mplayer it is simple to convert an ASF file to MP3. Ensure you have mplayer installed (On CentOS this would be "yum install mplayer"). mplayer infile.asf ...
• How do I verify an EU VAT number?
  EU VAT numbers can be verified at the VIES site. ...
• How do I list all packages and versions on Ubuntu?
  To list installaed software and the versions numbers first install apt-show-versions sudo apt-get install apt-show-versions They run apt-show-versions which will display currently installed software and versions. ...
• How do I boot a Supermicro motherboard using PXE?
  To boot with PXE you must first enable the network cards BIOS within your system BIOS and then when booting press F11 which will show ...
• How do I remove all lines from a file up to a keyword?
  To remove all lines up to and including a keyword from a file simply use sed as follows: sed '1,/keyword/d' infile > outfile (replacing keyword/infile/outfile with the ...
• How do I log into SmarterStats as the admin?
  To login into Smarter Stats as the admin user you need to use:   Site ID: admin Username: admin Password: <your password> You should now be logged into SmarterStats as ...
• How do I stop an automatic raid check?
  MD (software) raid checks are performed every Sunday at 1am on Centos6 systems, to stop a current raid check you can run the following command ...
• How do I log the connection IP in qmail (H-Sphere)?
  In versions newer than H-Sphere 2.5 Patch 1 you can increase the logging level by editing the "/var/qmail/control/options" file. Simply add (or edit any existing ...
• How do I find the serial/model number of a hard drive?
  To find the model or serial number of a hard drive you can use hdparm and the device name of the hard drive you need ...
• How do I copy the partition layout to a new drive?
  It's useful in RAID setups to copy the partition tables over to a second/third/etc drive to save using fdisk to set them all up. To ...
• How do I shutdown/stop an alien software RAID device?
  When using a tool suck as SysRescCD to access data on alien drives you may find you need to disable the RAID (i.e. to allow ...
• How do I see the progress of a dd?
  To view the current position of a dd you need to send signal SIGUSR1 You can either find the pid of dd and send the signal ...
• How do I pause/unpause shard balancing in MongoDB?
  During index creations and other long operations it is sometimes helpful to pause shard rebalancing. To pause/disable sharding connect with the console and run use config db.settings.update( { ...
• How do I see queued messages in qmail?
  To view a count of the messages in qmail    /var/qmail/bin/qmail-qstat   To view more details on the messages in the queue   /var/qmail/bin/qmail-qread   To view the message content take the # ...
• How do I stop X from starting on boot on the Iteaduino Plus?
  From the console you can disable X at startup by issuing the following command. sudo mv /etc/init/lightdm.conf /etc/init/lightdm.conf.disabled And then reboot the board. You will then find you ...
• How do I set/reset the Iteaduino Plus root users password?
  When logged in as "linaro" you can reset the root password with the following command   sudo password You will then be able to enter a new root ...
• How do I set/reset the linaro users password?
  If you haven't previously changed the linaro users password the default is "linaro", so you can reset the password by issuing the following command. passwd And enter ...
• How do I disable NetworkManager?
  If you want to configure your network devices manually via /etc/network/interfaces you can remove the service. Firtstly configure your network devices in /etc/network/interfaces and then ...
• How do I recompile the kernel (and install those missing modules) on the Iteaduino Plus?
  Install the required packages to recompile the kernel with (logged in as root) and prepare the directory for the source code.   mkdir ~/installed cd ~/installed apt-get install build-essential ...
• How do I find files sorted by last modified time?
      find . -printf "%CY%Cm%Cd-%CI%CM%CS %h/%f\n"|sort -n ...
• How do I find files sorted by last modified time?
      find . -printf "%CY%Cm%Cd-%CI%CM%CS %h/%f\n"|sort -n ...
• How do I update the email usage in cPanel for a single account?
  To update the mailbox usage statistics for a cPanel account simply run the following replacing "<USERNAME>" with the cpanel username. /scripts/generate_maildirsize --confirm --allaccounts --verbose <USERNAME> Statistics should ...
• How do I setup CentOS 7 for KVM Virtualisation with a bridged network [OVH/Hetzner]?
  Coming from a minimal install the first step is to install the required software # yum install net-tools qemu-kvm libvirt virt-install bridge-utils bind-utils Convert the network configuration ...
• How do I setup VNC for a user on Centos 7?
  To setup your server to run a full desktop VNC session first we need to install the required packages. yum groupinstall "GNOME Desktop";yum install tigervnc-server xorg-x11-fonts-Type1 Once ...
• How do I make a KVM Virtual Server start on reboot?
  Run the following command replacing SERVER_NAME with the name of the VM. virsh autostart SERVER_NAME You should then be notified the Domain has been marked to auto ...
• How do I use a static network device name for KVM (to graph in Cacti for example)?
  To force a static (pre-defined name for a KVM Virtual Machine you will need to edit the configuration file for the VM (replace VM_NAME with the ...
• How do I configure KVM to suspend/restore virtual machines when the host is rebooted?
  To suspend a VM on host shutdown you will need to configure the following file vi /etc/sysconfig/libvirt-guests Set the following options (which are located throughout the configuration ...
• How do I change the timezone on Centos 7 to UTC?
  CentOS 7 now includes a tool to change the timezone, to view your current timezone run the following command. timedatectl This should display the current timezone configuraton. ...
• How do I setup SNMPd on CentOS 7?
  To setup SNMP daemon firstly install the required packages. yum install net-snmp net-snmp-devel net-snmp-libs net-snmp-utils Then edit the main configuration file vi /etc/snmp/snmpd.conf Find the line starting with "com2sec" ...
• How do I rename a KVM VM?
  This example works on CentOS 7, but will likely work on other distributions too.   Save a copy of the Virtual Machines configuration (replacing VMNAME with the ...
• How do I install the same RPM packages on a new server as an old?
  First you need a list of the packages on the old server. rpm -qa --qf "%{NAME}\n" > rpmlist.txt   Copy this file to the new server (for example ...
• How do I get the disk usage of a directory including hidden directories/files?
  Using du with a wildcard would not normally include "hidden" directories/files (those starting with a dot). But you can show the usage with this simple ...
• How do I alter the kernel cmdline and rebuild grub2 on CentOS 7?
    The kernel command line (cmdline) can be edited in "/etc/default/grub" (GRUB_CMDLINE_LINUX).   Once edited you will need to rebuild the config for grub2 using the following command   grub2-mkconfig --output=/boot/grub2/grub.cfg   You ...
• How do I enable autologin on TTY running on the Gadget Mode serial port?
  The Cluster HAT allows you to log into the Pi Zeros via the (Gadget USB) Serial port, sometimes it's helpful to skip typing in the ...
• How do I create and copy the SSH key from the Controller Pi to the Pi Zeros to allow passwordless logins?
  Assuming you haven't already created a public/private key on the Controller Pi run the following. ssh-keygen -t rsa Newer Raspberry Pi OS installations allow you to use ...
• How do I copy the partition table from disk to disk?
  When using GPT you can use sgdisk to copy the partition table. FROM="/dev/sdX" TO="/dev/sdY" sgdisk $FROM -R $TO sgdisk -G $TO This will copy the partition table over and set ...
• How do I copy SSH keys to P1-P4 when using usbboot/rpiboot?
  Since the filesystems for P1-P4 are stored on the Controller it's even easier to setup SSH keys to log into the Pi Zeros without using ...
• How do I enable autologin on TTY running on the Controllers serial port [Raspbian Stretch]?
  To enable auto logins on the TTY running on any serial port on the Controller log in and run the following command and reboot. sudo sed ...
• How do I show disk usage breakdown including hidden directories?
  Using "du" with the following options will show usage of all files and directories including hidden (those starting with a dot). du -sch .[!.]* * ...
• How do I setup NAT on the WiFi interface on the rpiboot test images?
  WARNING: These steps relate to the OLD test rpiboot (only) images and NOT the current combined images, if you want NAT on the current image ...
• How do I force apt to connect using IPv4 (or IPv6) only?
  To  connect using IPv4. apt -o Acquire::ForceIPv4=true update Or to use IPv6 only. apt -o Acquire::ForceIPv6=true update ...
• How do I enable mDNS/zeroconf/Bonjour on Armbian?
  To allow <hostname>.local domains to be resolved on Armbian install the following. sudo apt-get install avahi-daemon libnss-mdns libnss-mymachines You should then be able to resolve domains using ...
• How do I USBBOOT Pi Zero/Pi Zero 2 without SD cards (Cluster HAT/Cluster CTRL)?
  With the Cluster CTRL images (linked from the ClusterHAT website) it's now possible to mix/match booting nodes (Pi Zeros/Compute Modules/A+) with or without SD cards. Preparation This ...
• How do I change a Cluster CTRL image type (Controller/NAT/P1/P2/P3/P4/etc.)?
  If you're using an older style Cluster HAT image (if you have /etc/default/clusterctrl then you're using the new style), follow the ClusterHAT instructions. On the Cluster ...
• How do I change a Cluster HAT image type (Controller/NAT/P1/P2/P3/P4/etc.)?
  If you're using an newer style Cluster CTRL image (the file /etc/default/clusterctrl exists) please follow Cluster CTRL instructions. On the Cluster HAT images there are three ...
• How do I resize a disk image (Raspbian SD/USB image)?
  To resize the last partition in a disk image, for example a Raspberry Pi SD card image first increase the size of the file on ...
• How are nodes numbered with Cluster CTRL/Cluster HAT (resolve order conflict)?
  The pX number of a node for control is set by it's priority (this might not be the same as the hostname/configuration of the image/usbboot ...
• How do I write new firmware to Cluster Triple?
  Control of the Cluster Triple is done using an ATmega328P (or ATmega328PB), the IC can be reprogrammed using either a standard ISCP programmer or you ...
• How do I enable autologin on TTY running on the Controllers serial port [Raspbian Buster/Bullseye]?
  To enable auto logins on the TTY running on any serial port on the Controller log in and run the following commands and reboot. sudo mkdir ...
• How do I run a backup for a single account in DirectAdmin?
  Set the USER variable to the account name to backup. USER="example" echo "action=backup&append%5Fto%5Fpath=nothing&database%5Fdata%5Faware=yes&email%5Fdata%5Faware=yes&local%5Fpath=%2Fhome%2Fadmin%2Fadmin%5Fbackups&owner=admin&select%30=$USER&type=admin&value=multiple&when=now&where=local" >> /usr/local/directadmin/data/task.queue   ...
• How do I tell a Raspberry Pi to ignore a HAT EEPROM?
  To prevent loading of device tree files (etc) from a HAT EEPROM add the following to the config.txt file in the /boot partition. force_eeprom_read=0 ...
• How do I stop the HAT EEPROM being loaded on a Raspberry Pi?
  To prevent the device tree configuration from being loaded from a Raspberry Pi HAT add the following to your config.txt file. force_eeprom_read=0 ...
• How to I setup a login prompt using the USB-USB Null Modem?
  To allow you to login to a Linux machine over the USB-USB Null Modem a getty needs to be ran on the end you're trying ...
• How do I use the solder jumpers on the Cluster HAT?
  Solder jumpers on the Cluster HAT allow you to modify the default behaviour and configuration. To change the configuration you will need to either cut ...
• How do I use the FAN header on Cluster HAT v2.5?
  The FAN header on the Cluster HAT v2.5 is controlled via GPIO pin BCM18 (set to output and set high to turn the fan on, ...
• How do I manually install clusterctrl?
  If you're using one of the provided ClusterCTRL images the cluserctrl tool will already be installed but those using the ClusterCTRL Stack or only want ...