• How To Completely Disable ufw in Linux Ubuntu Mint Debian


    This is for the situation that you're doing other things that may conflict or have your own custom rules and ufw keeps overriding iptables. A lot of guides don't work, and even ufw reset does not work, because it still leaves the old ufw chains. Here is what works to disable ufw completely systemctl stop ufw systemctl disable ufw ufw disable rm -f /et........
  • How to remove metadata from pdf on Linux Ubuntu


    Install exiftool: apt install exiftool Remove the metadata from "thefile.pdf": exiftool -all= thefile.pdf Warning: [minor] ExifTool PDF edits are reversible. Deleted tags may be recovered! - thefile.pdf 1 image files updated Metadata, in the context of PDFs, refers to a set of data that describes and gives informat........
  • Thunderbird Attachment Download Error Corrupt Wrong filesize of 29 or 27 bytes Solution


    This is an ongoing issue even with the latest Thunderbird 102.x where attachments downloaded via IMAP just won't save or will be corrupt which is a huge interruption to workflow or if you come back later to find out the file you thought you saved is invalid/corrupt and you have perhaps deleted the e-mail. How to solve the Thunderbird filesize attachment issue? 1. Click on "Settings". then go to "General". 2. Scroll to the bottom to find "Conf........
  • docker / kubernetes breaks Proxmox QEMU KVM Bridge VMs


    Docker adds iptables rules that break a lot of things including MASQUERADE or anything that needs the FORWARD table. If NAT is not working after Docker installation, it is probably because it set the iptables FORWARD policy to DROP. This may also make you think that your br0 or bridge is not working, but it's likely just due to what we'll mention later on below, that, Docker probably set your FORWARD chain to default DROP all packets, so nothing on your bridge ever makes it out........
  • ?? Question Marks for time, permissions and size of a file?


    -?????????? ? ? ? ? ? shadow ----------. 1 root root 748 Jul 10 04:35 shadow- cat: shadow: Input/output error If you see this you are probably in big trouble, it could be a physical error or if it's a VM image that it is corrupted due to a physical error on the underlying disk/array/NAS or it could a........
  • Cisco Switch Reset To Factory Defaults


    This works on the 2000 and 3000 series generally. *The easy way is to just hold the mode button for 10+ seconds. The full/proper way is below: 1.) Either power on the unit and hold the "mode" button or hold the "mode" button until you see the below: 00:04:08: %SYS-7-NV_BLOCK_INIT: Initalized the geometry of nvram 00:04:08: %EXPRESS_SETUP-6-CONFIG_IS_RESET: The configur........
  • Linux partprobe/partx cannot access last and 4th partition


    On a test machine Iwas never able to access to a newly created 4th partiton. As we can see there are dev devices for everything but the 4th partition. The normal "partprobe" or "kpartx" or kernel being told to rescan the block device didn't help (only a reboot did). fdisk -l /dev/sda Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders Units........
  • Mozilla Firefox Address Bar History Not Working places.sqlite corruption solution database repair


    Here is the only solution Ifound that works in Firefox: *Note you could basically just copy all of the commands in bold (the rest just shows the output) Install sqlite3 sqlite3 places.sqlite sqlite> .clone places.sqlite-fixed moz_places... done moz_historyvisits... done moz_inputhistory..........
  • vbulletin 4.2.5 after upgrading from 3.6 white screen fatal php errors


    The code may lead you to believe you have an incompatible template but if you are not trying to use an old template currently that is not the issue. I actually deleted all 3.x style templates to make sure. What the issue is, is old plugins that are not compatible but Vbulletin does not seem to account for this except that you'll see a fatal PHPerror. You should disable all plugins and then enable one by one until you find the one that is causing the issue. &........
  • USB 3.0 External HDD Enclosure Seagate UAS problems - [sdd] tag#1 CDB: Write(16) 8a 00 00 00 00 01 70 04 08 68 00 00 00 08 00 00


    This is a 8TB Seagate external USB 3.0 device apparently newer kernels use a module called "UAS" instead of "USB Storage" which causes issues as a lot of devices are not properly supported in UAS mode by the kernel driver. The solution some say is to disable UAS specifically for your USB device but I'd rather just disable UAS altogether. Solution blacklist UAS: *do not do this it does not work and just causes your USB 3.0........
  • Linux How To Recover Partition Table from Kernel and Restore Centos/Debian etc..


    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:........
  • Linux free space not reclaimed after deleting large log file solution


    This example involves an Aterisk message log of about 26GB, but with any server it usually does not get deleted until the server is stopped/restarted: asterisk 13729 root 6w REG 0,41 27277943090 59097971 (deleted) /var/log/asterisk/messages So if you've deleted a bunch of large logs, make sure you restart the server for them to regain your space. ........
  • MySQL Allows blank user with no password to login


    I just realized I have some blank users which I deleted butI can still login to this dummy account without a password for some reason. mysql -u -p Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 5 Server version: 5.1.69 Source distribution Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation an........
  • LSI MegaRAID Adventures, Guide and HowTo


    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........
  • kvm cannot boot xen guest using lvm


    This booting error is because the Xen PV guest image uses the Xen kernel, this is not compatible with anything but a host running a Xen kernel. I did a kpartx -av virtual.img and then it created some partitions that showed up in fdisk. I mounted it and did a chroot into it and removed the xen kernel and installed a normal kernel but Xen still shows the same kernel in Grub (only the Xen one). This is strange but it seems like this Xen PV guest has some sort of hidden or........
  • CPanel error: "Your SSL certificate failed to install on your site."


    This error in my experience is user error although CPanel doesn't help, this message doesn't give you much to go on. Let's talk more about the process of setting up SSL with CPanel. Your site must have a dedicated/non-shared IP to even have the option of creating an SSL Certificate. You must create a Private Key (do not delete this private key!) You must create a CSR (Certificate Signing Request) Use CSR to create cert........
  • Linux High IOWAIT updatedb can't be killed and crash with mdadm


    high IO wait 424 root 39 19 1900 848 552 D 0.0 0.0 0:00.91 updatedb root 424 0.0 0.0 1900 848 ? DN Mar11 0:00 /usr/bin/updatedb -f sysfs?rootfs?bdev?proc?cpuset?binfmt_misc?debugfs?sockfs?usbfs?pipefs?anon_inodefs?futexfs?tmpfs?inotifyfs?eventp........
  • MySQL NEVER delete ib_logfile0 or ibdata1 or you'll lose data


    don't delete /var/lib/mysql/ib_logfile0 or ibdata1 or mysql won't restart I didn't realize they were internal and not part of replication like the relay files! /usr/libexec/mysqld: ready for connections. Version: '4.1.22-log' socket: '/var/lib/mysql/mysql.sock' port: 3306 Source distribution 110127 16:31:00 [Note] /usr/libexec/mysqld: Normal shutdown 110127 16:31:00 InnoDB: Starting shutdown...........
  • PHP5 & Apache Blank/White Screen/Page PHP won't work


    PHP5 & Apache Blank Screen/Page The PHP package is installed and works from the CLI Error reporting is enabled The only way I could get it working was: rm /etc/php.ini yum remove php yum install php-* -x php-pear* -x php-pecl* Interestingly enough reinstalling php did not bring back the deleted php.ini but everything is working. ........
  • mdadm won't boot due to fsck error


    Nov 29 20:17:58 ubuntu kernel: [ 1157.180789] md: md1 stopped. Nov 29 20:17:58 ubuntu kernel: [ 1157.180829] md0: unknown partition table filesystem not responding/reading properly with du or rsync (this needed an fsck). [ 2571.489217] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923106 [ 2571.942299] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923110 [ 2571.9568........
  • jailkit for chroot ssh account security tutorial and fix for error


    This was done on Centos butI think it's easier on Debian machines, the paths that it is set to use are tailored towards Debian, so there is some fiddling that needs to be done on Centos. This is for chrooting ssh, but jailkit has other uses than just SSH jails but I won't cover them in this writeup. 1. Install jailkit yum install jailkit 2. Setup Jail Home mkdir /home/jail chown root:root /home/ja........
  • MySQL "Got error 28 from storage engine"


    I've gotten this error enough to bother posting about it, because I've come across so many servers where this happens, so what could "Error 28" possibly mean? Is your database corrupt, or is this a sign of a RAID failure/corruption or even worse, bad blocks on a clients system who has no RAID and never took backups? No, check your free blocks, it simply means you have no space. This was the result of a script that was overzealous and backed up the entire database........
  • SAMBA/SMB Share "Write" Access without Delete


    There is a nice mode that Samba supports which you can add to smb.conf create mode=555 This way users can create and write files/directories without deleting (except I believe dirs can be deleted but only if there are no files inside). It's too bad that Linux does not have built-in "write"/"delete" privileges and is something that even Windows 98 can trump.........
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