This guide assumes you have a working Postfix server and want it to sign with DKIM. There are a few things we have to understand to make all of this work though, which require you to be familiar with DNS as well. 1.) Install OpenDKIM apt install opendkim systemctl enable opendkim 2.) Edit /etc/opendkim.conf Syslog yes SyslogSuccess yes Mode&nbs........

You can do a static lease that is tied to the MAC address but what a lot of users prefer is that they come into the office or lab the next day and that their device gets assigned the same IP address (if possible). As we can see in the dhcpd logs that there is threshold that is defaulted as we'll show later. Whatever the threshold is set at, if the lease is younger than the threshold, it will keep the same lease. In other words, if the device goes to sleep or is powered off........

Are you getting this error when trying to connect to a site/domain/service and then you checked your router/nameserver's logs to see what's wrong? You may see something like this: named[3025898]: REFUSED unexpected RCODE resolving This is not usually an error with named or bind, at least not on your end but NORMALLY this is an issue with the remote nameserver. A lot of times this is a misconfigured remote nameserver. A classi........

Step 1.) Upgrade to Debian 11 first The process to go to Debian 12 is not as smooth as 11, when trying to upgrade from Debian 10. In fact, it doesn't work directly, so you'll first need to follow this guide to update to Debian 11, reboot and come back here if successful. Step 2.) Update sources.list Update your /etc/apt/sources.list like this: deb http://........

If you get this error, it is often because you have configured Apache with modules that weren't actually installed. Eg. you try to load the PHPmodule but didn't actually install the apache2 php module, so the server can't start. In general, this error can often be caused by issues with problematic modules and/or Apache being configured for modules that have not actually be installed (eg. libapache2-mod-php) is missing. The above results in this less than obv........

If you get this error in your logs: add bridge failed: Package not installed This error normally means one of two things. 1.) Is your brctl (bridge-utils) installed? On Mint/Debian check for "brctl". If it's not there do sudo apt install bridge-utils uml-utilities 2.) Is your bridge.ko (bridge kernel module loaded?). On some installs I have seen that you cannot modpro........

Be very careful about what filename you specify in dhcpd.conf if you get an error like this: NBP filesize is 0 Bytes PXE-E23:Client received TFTP error from server. If you specify "BOOTx64.efi" then the file had better not be called "BOOTx64.EFI" as it is case sensitive. It's really a case of th........

Have you checked your router/firewall logs and disconcertingly see connections to an unknown IP207.246.119.209:3478 from your Grandstream VOIPphones? You're not alone and the Grandstream forums have discussed this issue. However, even their own staff d........

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.........

Why choose OpenVPN instead of a firewall appliance? OpenVPN can be a reliable and easy replacement for traditional hardware or just be an additional tool that your company uses so that the firewall can focus on its job rather than acting as a VPNappliance at the same time. When comparing OpenVPN with traditional firewal........

It took a lot of fiddling to make a Huion Kamvas 13 Pro work in Linux but it simple once you know what to do. Don't bother searching as it is unlkely there is a guide out there that will actually make your tablet work. It mainly comes down to the fact that the hid_uclogic kernel module is buggy or doesn't support MANYof these wacom based/Huion tablets properly. What was happening with me is that Ihad the Kamvas 13 Huion setup as a secondary screen/monitor.&nb........

The key thing is that you must use a "machine"id of "pc-1.3" or it will say your hardware is not supported. Additionally you MUST use a virtio disk or you will get a ks_pre.sh error as soon as the install starts (a look at logs will show it can't find a disk). This is funny because even though the OS finds the disk and an fdisk -l shows it, it looks like the script looks for a /dev/vda device (virtio) and nothing else, so if you didn't use Virtio as you........

This is not about systemd/systemctl and not about "onboot" so there's no rc.local trick here but it's the GUI/Gnome etc when a user logs in that a command is launched. Put this in your home dir The .config/autostart directory is where Linux Mint/Ubuntu checks for autostart application config files mkdir -p ~/.config/autostart Create a new entry/file that starts an application........

In Debian a lot of times SSH disables the root user to login by password by default. This means you will get an authentication failure as if you typed in the wrong password. The logs also indicate the password is wrong but what is often the case is in the config file Check /etc/ssh/sshd_config cat /etc/ssh/sshd_config|grep -i permitrootlogin Make sure it says: PermitRootLogin yes If not change it and restart SSH........

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........

systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system. The key commands or arguments you will use with systemctl are the following: Unit Commands: list-units [PATTERN...] List loaded units &nbs........

zenity is a nice utility as part of the gnome window manager that allows you to script from bash and retrieve the input from the user. It could also be helpful in just notifying a user when they login with a popup window. I'll give an overview of what's available with zenity: Application Options: --calendar Display calendar dialog --entry Display tex........

Intel VT-X is enabled in Virtualbox but it doesn't seem to pass through the needed vmx extension despite the following variables on the host confirming it is enabled: cat /sys/module/kvm_intel/parameters/nested Y cat /sys/module/kvm_intel/parameters/ept Y OVF Tool: Disk progress: 99% OVF Tool: Transfer Completed OVF Tool: Powering on VM: Embedded-vCenter-Server-Appliance- OVF Tool: Task p........

Centos when copying old files and restarting it seems load everything fine and then says [FAILED] with no log or other message. service restart named named [FAILED] Check more thoroughly you may have missed the error if you have lots of zones! service named restart|grep error zone 1.168.192.in-addr.arpa/IN: not loaded due to errors. zone 2.168.192.in-addr.arpa/IN: no........

This is not the normal "black screen"issue and I was shocked to eventually find out why. The normal advice of reconfiguring Xorg didn't work. Even booting into "Recovery Mode" did not help. Here is the short end of the stick that fixed it: sudo apt-get install mdm mate-desktop-environment Yes you got it right, mdm and the mate-desktop-environment / gnome were somehow uninstalled. This must be whe........

This happened on Centos for no apparent reason with no obvious issue in the logs. Data could be read fine but not written (possibly due to some corruption or out of memory issue in the OpenVZ container is the best guess). All mysql update and insert queries failed freezing without any error log on any database and table. Tried to restart: service mysqld restart Timeout error occurred trying to stop MySQL........

sudo mkdir -p /etc/X11/xorg.conf.d/ sudo vi /etc/X11/xorg.conf.d/20-intel.conf On newer Ubuntu / Mint / Debian systems the file would go in: /usr/share/X11/xorg.conf.d/20-intel.conf Type "i" and enter the following: Section "Device" Identifier "Intel Graphics" Driver&n........

Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Missing folder chosen by user: Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Removed missing file: MAH02949.MP4 Jun 1 15:45:57 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: ui_util:WARNING Icon theme media-playback-start not found. Will use backup........

I was sure this was a Centos bug with OpenSSL, Apache, MySQL or even PHP. I tried everything but nothing helped. One clue is that if you check the Apache logs you will see nothing in the access logs until minutes later (this means Firefox has not even passed your request to the remote Apache/htttpd server). When even accepting the invalid certificate message that would show up minutes later when trying to "View the Certificate" Firefox would freeze. This bu........

Cannot even "Browse Network" when clicking on "Windows Network" Unable to mount location Failed to retrieve share list from server: No such file or directory logs: [2017/02/14 00:16:44.271314, 0] ../source3/nmbd/nmbd.c:58(terminate) Got SIGTERM: going down... [2017/02/13 17:35:41.797944, 0] ../lib/util/become_daemon.c:124(daemon_ready) &........

You are checking your MySQL logs in /var/log/mysqld.log and come across an error like this: 161222 18:03:40 [ERROR] /usr/libexec/mysqld: Table './eximstats/sends' is marked as crashed and last (automatic?) repair failed The Solution: cd /var/lib/mysql/eximstats myisamchk -r sends.MYI - recovering (with sort) MyISAM-table 'sends.MYI' Data records: 71129........

It is very handy to remember this and nice that the logs for all domains are in a central location: /usr/local/apache/domlogs........

Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason. Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to? In some cases on a remote system you can't easily reinstall without physical or KVM access. So in this case you add a second physical or disk or already ha........

What matters most about VPNproviders in 2024? We are highly suspicious of VERYLARGE VPN providers that have LOW PRICES and HUGE DISCOUNTS. The suspicion is that for those who know what costs are involved to purchase thousands of IPs and servers are not small. At the prices that many of the big mainstream providers offer, it is likely unprofitable or barely profitable. Then, how are those companies making money or is that even the goal? There use........

I used the matching 8.3.13 utilities and it didn't work but strangely the newer 8.3.16 which makes DRBD complain works just fine. GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by root@sighted, 2012-10-09 12:47:51  0: cs:SyncSource ro:Secondary/Primary ds:UpToDate/Inconsistent A r-----     ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:5236960   &am........

http://deepxw.blogspot.ca/search/label/Universal%20Termsrv.dll%20Patch The above site has the patch that does this essentialy turning a Desktop Windows into a full fledged RDP server.........

[Wed Jan 08 18:50:07 2014] [emerg] (28)No space left on device: Couldn't create accept lock (/etc/httpd/logs/accept.lock.15449) (5) This may happen when trying to restart Apache and you find it dies right after starting and check /var/log/httpd/error_logs. What is the cause of this? You could be out of disk space (if you're not then see #2 and below) You're out of Semaphores, you need to kill all the old ones.........

All Errors (CPanel does not report by domain, but puts everything in a single log which Ithink is a bit silly and annoying): /usr/local/apache/logs/error_log Access_Logs They are found within the home directory of the site user eg.: /home/admin/access-logs/yoursite.com MySQL Logs /var/lib/mysql/yourhostname.err........

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. ........

A lot of people become nervous (and understandably so) when checking their auth or security logs, in Centos /var/log/secure and see dozens, hundreds of even thousands of attempted logins to various services, especially SSH. Of course you could manually block these people/IPs but no one has time to read the logs like that, what if some program or script could do it for you? This is what denyhosts does for you, it checks the logs and based on a certain number of failed SSH attem........

I'll start by showing some problems in the logs: [2011/08/07 16:22:06, 0] param/loadparm.c:8569(process_usershare_file) process_usershare_file: stat of /var/lib/samba/usershares/movie failed. Permission denied [2011/08/07 16:22:06, 1] smbd/service.c:676(make_connection_snum) create_connection_server_info failed: NT_STATUS_ACCESS_DENIED That means you don't have permission to access the fi........

One thing to note about DNS servers and providers is that they aren't always trustworthy, not even if they're Google or your favorite ISP. Any DNS server can compromise your privacy, and they are likely tracking your browsing habits and keeping logs of it. Sometimes it's for Marketing/Research purposes such as Google's GMail service which they admit is scraped/datamined. I would expect nothing less from their DNS service. The other danger with such widely used and pu........

You need to enable the httpd daemon with monit to actually view the status and control, it's not only for the web interface since the httpd is theONLY way of controlling monit and viewing the status. monit monitor all will also reinstate disabled services if they've timed out too much. Just restarting the service will do nothing to re-monitor a service that monit has stopped monitoring due to too many failures. *Also note that /etc/monit.conf i........

yum exits in the middle The problem is this VPS seems to be an OpenVZ template from HyperVM. The only way to make it work was to disable i386 packages since this was an x64 kernel. That shouldn't be necessary but it was the only way to make yum stop quitting after the first package or two. I couldn't find any issue by checking the logs either. echo y|yum install vim-minimal telnet expect jwhois net-tools slocate iptables elinks gawk L........

After an upgrade wine wouldn't open anything, not even the pre-installed notepad. There are no wine logs and nothing is mentioned in any standard log file about why. I finally decided to run wine from the shell and see what's going on: wine client error:0: version mismatch 398/402. Your wineserver binary was not upgraded correctly, or you have an older one somewhere in your PATH. Or maybe the wrong wineserver is still running?........

I thought there would be an error message or warning from MySQL in the case that the text you submit is greater than the allowed limit based on the field. So essentially I submitted text that was about 120,000 characters long, whereas the limit of TEXT is just 65,535 characters! I almost lost half of my data/what I typed without knowing it! I just altered the field type in my database from TEXT to LONGTEXT. I can't see how LONGTEXT wouldn't be long enough for MOST........

It's basically free bash shell script available from: http://wpkg.org/email2fax/index.php/Main_Page Make sure you have the required tools: libtiff ghostscript mpack/munpack Where you can e-mail your Asterisk box and it will fax it to the phone number in the subject line. The good news ends there, it is fairly undocumented and buggy. Take for example how the documentation mentions you can invoke from the com........

Proxmox has made this free utility to backup running OpenVZ containers. It's a great program which is actually just a PERL script but gets the job done. This program is not 100% required because all it really does is cp -a from your container's path as far as I know but it is still good to have uniformity to how you backup your containers. For RPM distros such as Centos/RHEL/Fedora etc.. download and install this: wget http://www.proxmox.com/cms_proxm........

heartbeat is stopped for some reason Anyway hnode2 was active and the services are running fine but I see heartbeat has been stopped somehow. Here is the last log I see of heartbeat: [quote:23c84415f5] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: MSG stats: 9/1762471 ms age 0 [pid16738/MST_CONTROL] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: cl_malloc stats: 716/51784021 152624/74519 [pid16738/MST_CONTROL] Sep 9 17:15:32........

Put what you see below into your .htaccessand it will enable errors and notices. (change on to off and 1 to 0 to disable though) php_flag display_startup_errors on php_flag display_errors on php_flag html_errors on Now you'll be able to see errors and notices but this should really only be used for debugging purposes and only temporarily as it can be a security issue since errors can reveal information you wouldn't want hacker........

Inever saved any of the logs, but basically no matter what OS (Linux)I used, I could not get my 1000GB hard drive to work (Seagate SATA). The BIOS recognizes the drive and fdisk -l shows the hard drive as it should. The tricky thing is that different OS's will give you different results, but don't be fooled. You can't use these larger drives for long. Iwas getting all kinds of seek/IOerrors and also messages that the port could not be read.........