• How To Shrink Dynamically Allocated VM QEMU KVM VMware Disk Image File


    Let's say you have a VM file that uses 200G of dynamic space, but really only has 40G in usage. If you add fles and delete, at some point the file will be larger than the current space you are using. Take this image which shows is using 71G of space on the host: The actual space being used inside the image is about 43G as we can see:........
  • Docker Tutorial HowTo Install Docker, Use and Create Docker Container Images Clustering Swarm Mode Monitoring Service Hosting Provider


    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.........
  • gsmartcontrol for Windows to Check the SMART S.M.A.R.T status


    gsmartcontrol is a free tool that let's you see the status of the SMART parameters so you can check things like temperature, reallocated sectors, bad sectors etc.. to give you a better idea of your drive health. Download it here. gsmartcontrol is a very useful tool in Windows to check your HDD / Hard Drive health status. In my experience you should NEVER trust that everything is OK just because SMAR........
  • LVM How To Create Pool (dynamically allocated and not fully allocated)


    The main use I have for this is virtual servers being able to use an LVM volume but not occupying all of the space. It saves time in deploying machines and copying them so you are only copying the space they are using (eg. 5GB / 60GB vs the full 60GB). There are some disadvantages which is mainly the fact that thin pools by their nature allow you to "overallocate" disk space which is that you could use more space than is available on the disk itself and corrupt your data........
  • Why SMART is not smart at all and doesn't properly predict disk errors that cause a kernel panic or crash


    Before getting into the output here is my typical experience with SMART, there is what I call a "bad disk" with pending and uncorrectable sectors that cannot be reallocated. It has caused a kernel panic and system crash repeatedly as we can see from the logs. But SMART says it has "PASSED" its self assessment. SMART is still useful to me but it is more about looking at Current_Pending_Sector. Any time I have had anything but 0 for that attribute it........
  • How Does Cisco CUCM (Cisco Unified Communication Manager) Work?


    Cisco's CUCM (Cisco Unified Communication Manager) is a system that combines voice, video, data and mobile products into a single unified management suite. At its core, the CUCMis like a "Super PBX" that controls the flow of all communications through an organization even single or multiple site deployments. Cisco's CUCMmakes communication more effective and simple through centralized management and unification of communications resources.........
  • mdadm and lvm how to completely disable and remove vg/pv/lv


    In short the solution is just to use vgremove for the actual /dev/mapper device: vgremove /dev/mapper/backups-backuplv box mnt # mdadm --manage /dev/md8 --stop mdadm: Cannot get exclusive access to /dev/md8:Perhaps a running process, mounted filesystem or active volume group? box mnt # lv lvchange lvconvert lvcreate l........
  • Windows showing wrong drive size after resizing the VPS/image or cloning howto fix


    How to Increase The Disk and Partition Size in Windows 2022,2019,11,10,8,7 etc.. Server 1, Enter the command prompt Start -> cmd 2. Start diskpart diskpart 3. Find the drive that has the wrong size list volume 4. Select the volume (in this example we use volume 2) select volume 2 5. Extend the volume........
  • LVM Tutorial how to create a Physical Volume (PV), Volume Group (vg), and a Logical Volume (LV) within it


    # first we need a physical volume which we use the pvcreate tool to create # I create mine on /dev/sdb3 pvcreate /dev/sdb3 dev_is_mpath: failed to get device for 8:19 Physical volume "/dev/sdb3" successfully created # pvdisplay shows the newly created volume pvdisplay "/dev/sdb3" is a new physical volume of "1.35 TiB" --- NEW Physical volume --- PV N........
  • Fatal error: Out of memory (allocated 6291456) (tried to allocate 7680 bytes)


    Fatal error: Out of memory (allocated 6291456) (tried to allocate 7680 bytes) This is usually caused by Wordpress, Drupal or other ridiculously inefficient CMS' out there, as a temporary fix you can increase PHP's memory limit but it's best to find the actual culprit, by disabling add-ons and other scripts etc...........
  • WD 20EARX Dead Again


    Another new drive bad from the start: Jun 2 15:14:18 one-desktop kernel: [15895.386779] ata2.00: exception Emask 0x50 SAct 0x1 SErr 0x280900 action 0x6 frozen Jun 2 15:14:18 one-desktop kernel: [15895.386782] ata2.00: irq_stat 0x08000000, interface fatal error Jun 2 15:14:18 one-desktop kernel: [15895.386784] ata2: SError: { UnrecovData HostInt 10B8B BadCRC } Jun 2 15:14:18 one-desktop kernel: [15895.386788] ata2.00: cmd 60/0........
  • WD 20EARX 2TB Bad within days


    This is just trying to read 5GB off the drive with dd and the drive initially tested ok but shortly after I wondered why I was seeing 2MB/s read speeds. Notice the "current_pending_sector", anytime I've seen it at anything above 0 even with no other bad fields/attributes, it means the drive is bad. ata1.00: exception Emask 0x0 SAct 0x3 SErr 0x0 action 0x0 ata1.00: irq_stat 0x40000008 ata1.00: failed command: READ FPDMA QUEUED ata1.00: cmd 60/00:00:........
  • Bad Hard Drive Slows Down Computer


    Here's a proven example of what a bad hard drive can do, it was technically functioning OKin a RAID array but the system became extremely low and the load become high and IOWAIT was even higher and I always thought it was a bad application. The truth is that this failing 1TBHitachi has slowly gotten worse and caused huge slowdowns, (eg. 100% load on Thunderbird waiting for e-mails to load etc..). After swapping it out, tabs change instantly, emails are not lagged, and........
  • How To Test If Your Hard Drive Is Good/Signs of dying hard drive


    I like dd, although it only reads it, usually a read test of the entire disk will uncover if your hard drive is bad in some parts. This is a good thing to do at least once a month, a lot of times bizarre program behavior, laginess and crashing/unnmounting problems etc.. are due to a failing disc and SMART won't know it or indicate a problem: We must also remember there's never a guarantee, I've found that ever since we moved to larger and more platters per drive with 1TB drives........
  • smart is not smart, it thinks a dead drive is still good


    I had a dying drive that smart thought until it totally disappeared was a good drive, and actually all parameters did look fine but this system was causing my system to lockup and other bad behavior: === START OF INFORMATION SECTION === Device Model: WDC WD20EARS-00MVWB0 Serial Number: WD-WMAZ20139 Firmware Version: 50.0AB50 User Capacity: 2,000,398,934,016 bytes Device........
  • Hitachi 2TB HDS5C3020ALA632 drive DOA


    I had one of these shipped and it was not recognized when plugged in, here's what a dead drive looks like (I assume it's teh circuit board which is dead): ata1: link is slow to respond, please be patient (ready=0) ata1: softreset failed (device not ready) ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) ata1: link online but device misclassified, retrying ata1: link is slow to respond, please be patient (ready=0) ata1: softreset f........
  • WD (Western Digital) Advanced Format Drive Lagged/Slow Speed/Performance/Design Flaw EAD/EARS problem WDC WD20EARS-00S8B1


    Let the numbers speak for themselves, from what I read the Load_Cycle_Count which is very high (more than 500,000/half a million times) is the number of head parks. What a stupid"Green" design and design flaw which will probably mean an early life for the drive. This is almost as silly as Seagate's new reputation for BSY/poor quality disks since the 7200.11 series. To make it worse this is also when Western Digital introduced "Advanced Format" o........
  • Seagate Drive 500GB Drive Dying


    This drive is clearly on the way out, the Kernel knows it but I'm surprised that SMART is not concerned. I didn't blame Seagate for their past issues until now. This hard drive has hardly been used and has not even been powered on for a year according to SMART. Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.11 Device........
  • Seagate 7200.11 firmware defect in 500GB, 1000GB (1TB) and 1500GB (1.5TB) Hard Drives


    Seagate Inventory/Firmware Check I heard about this issue a long time ago but never looked into it. I figured I wasn't affected since my 500GB drives were running for so long. I've been using Seagate's since 2002 and to this day all of the drives I have are alive from Seagate. *Update the bad news is that I realize one of my 500GB's is about to die, it's not even a year old, but is also not affected by the recall according to Seagate! Seagate Inventory/Firm........
  • Basic Port Listing


    Basic Port ListingHopefully someone finds this useful or at least interesting. http://www.sans.org/top20/#u9 Name Port Protocol Description Small services ........
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