• Local Vs Universally Administered MAC Address NIC Refuses to come up


    2,6,A or E is what the second digit of your MAC address must be otherwise a lot of OS's will not work. They will say the NIC is down/not connected even though it is. This is because if the second digit is not set properly it will not view as a valid MAC or device uplink. This is especially an issue with VMs whether in QEMU etc.. if you are making your own MAC. MAC address is invalid c4:d1:aa:e5:10:05 To fix it just........
  • LUKS Hard Drive Encryption on Linux Mint Ubuntu Debian etc how to mount encrypted hard drive


    The key thing here is to know the actual partition that is encrypted. Often in Linux Mint's installer that ends up being partition 5 or /dev/sda5 sudo cryptsetup luksOpen /dev/sda5 anynamehere You will then be prompted for your irrecoverable passphrase: Enter passphrase for /dev/sda5: If all goes well it won't say anything further. If it says ""No key available with this passphr........
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    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........
  • Linux What is umask (user mask) for file and directory creation permissions and how to calculate umask and change the defaults


    umask are the default permissions that are applied when a file or directory are created. To see this in action simply just "touch filename" or "mkdir somedir" and you'll see what default permissions are applied. The first thing Ialways tell people you should know is to NEVER change the defaults unless you are making them more restrictive. But they work well and if you change the defaults you could end up creating a file without permission to read........
  • vmkping -I vmk1 10.0.2.69 PING 10.0.2.69 (10.0.2.69): 56 data bytes sendto() failed (Host is down)


    [root@localhost:~] vmkping -I vmk1 10.0.2.69 PING 10.0.2.69 (10.0.2.69): 56 data bytes sendto() failed (Host is down) vsphere distributed switch vmotion not working [root@localhost:~] esxcfg-route -l VMkernel Routes: Network Netmask Gateway Interface&........
  • VMWare vSphere 6.7 Errors Solution 503 Service Unavailable (Failed to connect to endpoint:


    503 Service Unavailable (Failed to connect to endpoint: [N7Vmacore4Http20NamedPipeServiceSpecE:0x00005556ba09c070] _serverNamespace = / action = Allow _pipeName =/var/run/vmware/vpxd-webserver-pipe) 503 Service Unavailable (Failed to connect to endpoint: [N7Vmacore4Http16LocalServiceSpecE:0x00007fd26000b240] _serverNamespace = /ui action = Allow _port = 5090) Errors like the above are usually because there is an issue with your vSphere or more commonly it i........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands


    [root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........
  • VMWare Vsphere VCSA Graphical Install Creates json


    yes it does create its own json ============================================ cat /tmp/vcsaUiInstaller/ovftool-20180809-175238948-20180809-175603497.log |grep -i json 2018-08-09T17:56:04.238-07:00 verbose OVFTool[30966] [Originator@6876 sub=Default] Manifest file entry: SHA1(VMware-vCenter-Server-Appliance-6.7.0.12000-8832884_OVF10-file1.json) = 1deb658c724767697587d5909c4051c01813e6a1 --> ........
  • VMWare Hardware virtualization is selected and cannot be deselected due to selection of VBS Insufficient resources to satisfy configured failover level for vSphere HA.


    There is no such option as "VBS" that Ican see in vSphere 6.7 Ibelieve this is actually an issue because of using old hardware in this case L5420 doesn't support Nested Virtualization I believe. Hardware virtualization is selected and cannot be deselected due to selection of VBS Insufficient resources to satisfy configured failover level for vSphere HA.........
  • ImageMagick How To Convert Specific PDF Pages or a Range


    A very handy feature of ImageMagick's convert command is that it can convert PDF's to other image formats like jpg but did you know you can even manually select a range or specific pages from the PDF? Here is an example of converting a range of pages from a PDF in this case pages 25 to 36: convert -density 300 "vSphere 6.5-1.pdf[25-36]" vsphere.jpg Here is an example of converti........
  • How to qemu-kvm enable bridged networking in Debian Ubuntu Linux Mint on KVM containers


    I've read a few guides about this but they didn't work for me. sudo apt-get install bridge-utils #don't think the above is enough it won't work still even though you have by default an /etc/qemu-ifup that handles it if you have the right tools and setup sudo qemu-system-x86_64 -net tap -net nic -enable-kvm -cpu host,vmx=on ~/VirtualBox VMs/vsphere-vcenter/vsphere-vcenter.vdi W: /etc/qemu-ifup: no bridge for guest interface foun........
  • VSphere InternalServerError - Error When Adding Permissions


    InternalServerError (com.vmware.vapi.std.errors.internal_server_error) => { messages = [LocalizableMessage (com.vmware.vapi.std.localizable_message) => { id = vapi.bindings.method.impl.unexpected, defaultMessage = Provider method implementation threw unexpected exception: com.vmware.vapi.std.errors.InternalServerError, args = [com.vmware.vapi.std.errors.InternalServerError] }], data = } I was getting the........
  • VMWare 6.7 VCSA VSphere ESXi Management SSO Install Guide on Linux using the CLI


    #mount the VCSA DVD mount /dev/sr0 /mnt/cd #alternatively you could mount the iso directly mount -o loop vcsa.iso /your/mount/path #for this purpose we are using the CLI installer on Linux cd /mnt/cd/vcsa-cli-installer/lin64 #no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file ./vcsa-deploy Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
  • Linux how to view video card make and exact model


    Normally lspci will show you just like this and would suggest they are exactly the same card: 1a:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/580] (rev e7) 1c:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/580] (rev e7) lspci -vnn is the answer As we can see one is a Gigabyte and the other is an MSI card. Wha........
  • Intel NUC Lower Power Green Computing Boxes Review/Comparison of J3160 and J3455 Models


    Intel NUC J3455 vs Vorke V1 J3160 Both are excellent units but the J3160 is nicer if you require even lower power usage (6W vs the Intel 10W). The price is attractive on the Vorke V1 as well. It's been said that the Intel J3455 NUC has a buggy BIOS and some other issues that require attention. The Intel J3455 is still nice because it has 2 RAMslots but it does get hotter due to lack of fan. The Vorke V1 runs cooler, uses less power an........
  • ffmpeg Linux Mint download, compile and install howto


    #if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used wget http://ffmpeg.org/releases/ffmpeg-3.3.2.tar.bz2 tar -jxvf ffmpeg-3.3.2.tar.bz2 cd ffmpeg-3.3.2/ ./configure --disable-yasm install prefix /usr/local source path ........
  • USB 3.0 PCI x1 Card Review VIA VL805 on Linux Review and Experience


    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........
  • Avocent DSR8020 KVM/IP - Network Connect Error - Solution


    This error is commonly due to Java security or TLS settings but there is a second issue with forwarded ports that also causes it. 1. Java Security/TLS Settings issue: This article has the solution to change them all in Linux automatically 2. Port Forwarding Issue if your Avocent DSR is behind NAT/private IP........
  • 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........
  • Samsung Galaxy Note Upgrade/Update Experience from 4.0.4 with aftermarket ROMs


    It really seems that 4.4.4 is not ready or stable for the i717 yet and this makes sense since it takes a lot of work/development and testing to get the factory stock ROMs working well. In the end I used the 4.1.2 based Blackstra BlackJelly because it was fast, stable and just works and feels great. The aftermarket support is great but many devs are focussed on adding features and customization that most of us don't want or need rather than getting things smooth and stable.........
  • OpenVZ mismatched kernel and dev when compiling.


    ./configure ./configure: line 91: cd: /lib/modules/2.6.32-042stab084.25/build: No such file or directory Error: kernel version not found. Please make sure your kernel is configured. dr-xr-xr-x. 4 root root 4096 Feb 21 06:13 .. lrwxrwxrwx 1 root root 45 Feb 21 06:13 build -> ../../../usr/src/kernels/2.6.32-042stab084.25 drwxr-xr-x 2 root root 4096 Feb 12 20........
  • Dell Perc 6/i SATA benchmarks without battery


    The results are not bad, the Hitachi performs the same as it does in a SATA2 motherboard. However, the 2TB is much different, on a similar 2TB Toshiba I get about 198MB/s on a different motherboard vs the 2TB Hitachi which should produce similar results. This Dell Perc 6/i is on a PCI x8 riser card and is connected to a 12-port backplane. Adapter #0 Enclosure Device ID: 32 Slot Number: 0 Enclosure position: N/A De........
  • LVM How-To Activate and Access Volumes/Data


    vgchange -ay 3 logical volume(s) in volume group "vg_12" now active lvscan inactive '/dev/vg_12/lv_root' [144.04 GB] inherit inactive '/dev/vg_12/lv_home' [1.00 GB] inherit inactive '/dev/vg_12/lv_swap' [7.85 GB] inherit........
  • Directadmin error/** Found 7 pre-existing rpmdb problem(s), 'yum check' output follows: e2fsprogs-devel-1.41.12-3.el6.i686 has missing requires of e2fsprogs-libs = ('0', '1.41.12', '3.el6') e2fsprogs-devel-1.41.12-3.el6.i686 has missing requires of l


    Solution To The Following: yum -y install zlib-devel yum -y install e2fsprogs* *** Cannot find /usr/include/et/com_err.h. (yum install libcom_err-devel) *** Installation didn't pass, halting install. Once requirements are met, run the following to continue the install: cd /usr/local/directadmin/scripts ./install.sh Common pre-install commands: http://help.directadmin.com/it........
  • Error: detected vswap CT config but kernel does not support vswap This means either old kernel or bad config (physpages NOT set to 0:unlimited) Solution for OpenVZ


    Error: detected vswap CT config but kernel does not support vswap This means either old kernel or bad config (physpages NOT set to 0:unlimited) Solution vzctl set $veid --physpages 0:unlimited --save........
  • LOG: MAIN PANIC failed to expand condition "${if eq {$authenticated_id}{}{0}{${if eq {$sender_address}{$local_part@$domain}{0}{${if match{$received_protocol}{N^e?smtps?a$N}{${perl{checkbx_autowhitelist}{$authenticated_id}}}{${if eq{$received_prot


    I experienced this with CPanel's Exim after an auto-update (a Google of this error produces lots of complaints with few clear solutions). In this case I'll put the solution at the top. Run /scripts/buildeximconf to rebuild the Exim config and it should be fine after that. mail -vs "from test" user@dest.com < .bash_history LOG: MAIN cwd=/root 4 args: send-mail -i -v user@dest.com LOG: MAIN &........
  • rpmforge: [#### ] 471/10722Segmentation fault yum[18934]: segfault at 0000000000000000 rip 00002ade62153a30 rsp 00007fff76f9fe58 error 4


    A few days ago this happened on multiple Centos 5 servers and apparently anyone using rpmforge was affected by this error and there was no solution other than disabling that repo to fix it. To some this highlighted a few points, that there is a reason RHELexists with full paid support, and also that this could be a vulnerability and huge flaw with yum. A yum search or install should not segfault just because the rpmforge repo goes down. Fortunately it came back up........
  • Kernel/make compilation time and how to improve compile times/compile the Linux kernel faster without hardware upgrades


    I thought only a faster CPUand SSDwould help but I already have a Quad-Core CPU and it wasn't being maxed out. The actual tests were performed on an AMD-V enabled 128MB dual core VMWare container though. There is a flag that can be passed to make in order to start multiple threads, by specifying 4 threads I was able to reduce the whole kernel compilation time from scratch by about 50%! (65minutes vs 31minutes!). *Yes I did do a make clean before each co........
  • 2011 Best Laptop - HP 15.6" Laptop featuring AMD Athlon II P340 Processor (G62-420CA)


    My mother needed a new laptop and I recommended her the same one I would have bought myself or my wife, that means the cheapest possible laptop with the most features for the money. This HP shines at this price point and one thing that made me stay away from buying more and recommending HP/Compaq was the poor battery life. Not anymore, this model has an industry leading up to 4 hours of battery life. Key Factors for Choosing It: HDMI Out........
  • 95th Percentile Billing vs Usage Billing, what's better?


    There are all kinds of threads and links on the internet, and this seems to be a contentious issue butI don't know why. 95th percentile is either a good deal for some or a big rip off for others, Ijust said it there :) But the reality is that for MOST people who transfer low amounts of data but burst to higher speeds such as 40mbit+ even for short periods of time, then you'll pay a lot of money to do that. Basically 95th percentile is an-old archaic method........
  • Apache MPM worker vs prefork


    find what MPM Apache is using, it will either be using "worker" or "prefork" apachectl -l Compiled in modules: core.c prefork.c http_core.c mod_so.c In my case it is "prefork" vi /etc/httpd/conf/httpd.conf Find the section that looks like this (by default one will normally exist for prefork and for worker, but in my case I only care a........
  • OpenOffice Calc SUM function not working Solution - Result is always 0/apostrophe appears in front of all numbers.


    I right clicked all applicable cells and chose "number" but that's enough. I notice when I click the cell there is an invisible ' in front of the number: '33.64 Calc imported my CSV and decided to add a ' in front of the numeric currency values!!!*Actually the problem occurs when you right click the cells and change the type from text to number, no matter what format you choose. If I change it to be currency i........
  • MySQL Replication/Dual-Master vs Clustering


    Many people aren't aware but recently Dual-Master Replication setups have become increasingly popular. That's because you get similar features and benefits of having a full-blown cluster (difficult to setup and maintain and requires I believe 3 servers just as controllers). With a dual-master you just have a different off-set for the keys and you should be good, but of course there is the chance that at some point replication will halt because of an unexpected or unforseen error........
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    Here is a RAID 1 partition (500GB Seagate & 2TB WD): Sequential Reads File Blk Num Avg Maximum Lat%&nbs........
  • Use rcconf to edit startup/init.d/init scripts on Debian/Ubuntu based distributions


    I've never understood how to enable and disable services for different run levels in Debian based distros, it's just weird, annoying and doesn't make sense. I much prefer chkconfig from RHEL. Just install the package called 'rcconf' and be done with it. rcconf makes things easy for you. apt-get install rcconf Reading package lists... Done Building dependency tree Reading state information... Done........
  • Unixbench Score on Core i5 750 with OpenVZ Kernel vs Xen/Openvz


    This was unbelievable how much the Xen kernel slows things down, keep in mind both tests were done on the hostnode, one was with the Openvz-Xen hybrid kernel and the other was just OpenVZ. You can see the performance difference is nearly 300% better when not using the Xen kernel. OpenVZ-Xen Kernel Test Results (I was wondering what was wrong/so slow with my Core i5!) # # # # # #&n........
  • Picking an FTPD (vsftpd) Server in Linux Centos/Debian


    I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find. yum search ftp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * rpmforge: ftp-stud.fht-esslingen.de * base: mirrors.netdna.com * updates: updates.interworx.info * addons: yum.singlehop.com * extras: mirrors.netdna.com rpmforge........
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    CVSUp the Easy WayIf you're reading this you probably have never used CVSUp or don't know how. CVSUp can be used for two things or just one if you prefer. *Keeping your kernel up to date *Keeping your port list up to date Start by editing the following file in: [b:76928b387d]vi /usr/share/examples/cvsup/cvs-upfile[/b:76928b387d] It can be quite overwhelming with all the crazy options. Basically there are only 3........
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    I bought a Dynatron A46G for my AMD X4 620 AM3 Quad Core CPU. Just judging by touch, the stock OEM fan/heatsink combo kept things so cool, I could leave the 1U server on the floor and it barely felt warm to the touch, including the heatsink itself. I thought the Dynatron A46G would be enough with passive cooling (it has no fan), but the same setup became burning hot on the underside of the server and also by touching the heatsink itself within minutes. I thought that th........
  • 1U Servers are Loud - We Have The Quiet Solution


    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........
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