This can break things easily in remove environments where it was normally easy to convert a normal eth0 to a bridge under br0, and that bridge would normally have the same MAC address by default, which is desirable for most situations.
In Debian 11 this is different for some reason now.
https://unix.stackexchange.com/questions/681013/bridge-gets-random-mac-........
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........
The passwords are stored in the following locations on Unix/Linux:
The directory is usually inside your home like this:
~/.mozilla/firefox
logins.json contains the locations, username and password
key*.db (usually then name could be key3.db or key4.db)
Without the key file you will not see any passwords in Firefox as it is required to in order to decrypt the contents of logins.json........
This error implies that there may be an issue with Xorg or maybe your NVIDIA GPU cannot start or initialize:
35 laptop kernel: [ 2031.857704] nvidia: loading out-of-tree module taints kernel.
35 laptop kernel: [ 2031.857724] nvidia: module license 'NVIDIA' taints kernel.
35 laptop kernel: [ 2031.857725] Disabling lock debugging due to kernel taint
35 laptop kernel: [ 2031.873280] nvidia: module verification failed: signature a........
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.........
Here is the scenario, you are using QEMU/KVM and are using something like the AC97 sound driver to pass the host audio to the guest via pulseaudio. This is useful because you can transparently pass your mic input from the host which means you can mute your microphone from the host, which prevents the guest from receiving any mic input even if unmuted.
Mute / Unmute Fix
This issue also seems to happen even if you press the mute button on the microphone and then unmute,........
There aren't too many simple guides that show you how to use commands to setup your USB or other drive as a normal bootable drive where you can easily boot custom kernels or whatever OS you would like.
1. Get the tools we need:
We install "syslinux" for MBR and "syslinux-efi" for EFI and "MBR" as we need a tool that embeds the actual MBR into our USB:
sudo apt install syslinux syslinux-efi mbr........
yum -y install gcc make gperf genisoimage flex bison ncurses ncurses-devel pcre-devel augeas-devel augeas readline-devel
checking for cpio... cpio
checking for gperf... no
configure: error: gperf must be installed
configure: error: Package requirements (augeas >= 1.2.0) were not met:
Requested 'augeas >= 1.2.0' but version of augeas is 1.0.0
yum remove augeas augeas-libs augeas-devel
wget http://downl........
MySQL on Debian versions is configured differently than the native local MySQL plugin so you will be disappointed when your password on the mysql client fails by default.
Here is how you reset the MySQL root password the proper and "working way"
#first we gracefully stop mysql
sudo systemctl stop mysql;
#then we forcefully kill any mysqld process just in case
sudo killall -9 mysqld mysqld_safe;........
It is fairly simple to use once you know how to use it. However, the tricky thing is that by default it doesn't seem to be active or listen on any interface on manually specified.
How To Install ifplugd
First we install ifplugd
sudo apt install ifplugd
Let's enable it on our desired device(s)
vi /etc/default/ifplugd
set this line as so:........
chroot which stands for change root allows you to virtually operate in another operating system even though you haven't booted it. It is commonly used to deploy new distros, applications and to fix a broken Linux/Unix install or prep a new system image without having to physically boot the drive or disk.
So in this example let's say we have a drive that has a Linux OS installed on /dev/sdb1 and we have mounted this partition on /mnt/sdb1
The key point is to edit the &quo........
If you see this in /etc/sudoers it is NOT a comment but an include.
#includedir /etc/sudoers.d
For example in Linux mint sudoers.d contains the following files:
casper mintupdate README
casper for example contains the following sudoers line:
mint ALL=(ALL) NOPASSWD: ALL
So if you are messing ar........
The reason for not being able to read one of these dreaded/ fillable "XFA" forms is because no Linux PDF reader that I'm aware of supports them. Part of this reasoning is for security. It is really silly, they should ban these XFA forms or at least replace the Please Wait with the non-fillable version.
Download Adobe Reader 9.5 for Linux from here:
This is the solution but only so much, at least for me I was able to view th........
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........
A simple way that may work for a lot of people who just need basic output for their scripts or daemons to announce an action is this:
echo "body or message" | mail -s "realtechtalk.com" user@domain.com
If you want to send a text file as the body just do this instead:
mail -s "realtechtalk.com" user@domain.com < /tmp/sometxtfile.txt
These are some ve........
Linux Set Date
date -s "YYYY-MM-DD HH:MM:SS"
date -s '2014-12-25 12:34:56'
BSD Unix Set Date
date yymmddhhmmss
date 170809121156........
Just a note before you do this you should have a sure, guaranteed way into the system such as local, KVMor preferably publickey making bruteforce SSH absolutely impossible since there is no password to bruteforce and even if someone knew the password they wouldn't be able to login except from the local console (presumably you should make sure no one unauthorized has physical access).
1. Edit /etc/ssh/sshd_config
Find the section like this:........
Solution:
Aptitude is very smart and fixed the issues it was because of nvidia cuda and opencl and nothing else suggested or hinted this using apt
sudo aptitude install wine
The following NEW packages will be installed:
ocl-icd-libopencl1{ab} ocl-icd-libopencl1:i386{ab} wine wine1.6
wine1.6-amd64{a} wine1.6-i386:i386{a}
The following packages will be REMOVED:........
#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 ........
At first I thought it's just not possible but there is actually an option that can be enabled to make symlinks work with Samba.
Then I put this under the [global] section
Note: It's "wide links" and not "wide symlinks" (some other sites have incorrect info which was a frustrating waste of time :))
Add this to your smb.conf
follow symlinks = yes
wide links = yes
unix ex........
Usually the cause is inexplicable because some things just don't work correctly even when calling all commands by their full path.
Usually adding the following to your crontab file at the top will fix/solve the issue:
SHELL=/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
........
For themes and custom CMS setups, the typical HTML theme is not ready to go at all but here are some common sed commands (search and replace that will get most of them working without breaking as you'd expect).
The problem is that often the theme directory will be separate from the content and this will break the relative paths that these themes use.
sed -i s/'href="'/'href="/themes/yourtheme/'/g index.html
sed -i s/'src="'/'src="/themes/y........
The Scenario
You have dual NICs and you disable NIC1 which uses 192.168.1.1 as its gateway. With NIC2 you enable it/connect it to another network which also has the gateway 192.168.1.1
Everything will work fine at this point.
When switching back to NIC1 even with NIC2 disabled and even unplugged, the OS basically can't pick up the new/updated ARP entry of the old device for 192.168.1.1 and perhaps thinks it is a security risk or spoof of some sorts and blocks i........
It is just the readlink command with the -f switch and it will display the full path, very handy to save time when you want to copy and paste the location of a file or script etc..
readlink -f updatehtaccess.sh
/var/lib/updatehtaccess.sh
........
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........
In my case I could login with the initial install but I rsync'd everything over while preserving ownership and permissions to another RAID partition and booted from that.was fine before. The problem is that you are kicked out the second you login and the problem was SELINUX for some reason (perhaps it noticed something strange when it was moved to the new partition)
login: pam_unix(login:session): session opened for user root by LOGIN(uid=0)
login: ROOT LOG........
sudo apt-get install zoneminder
[sudo] password for one:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
libuser-perl python-evince kdebase-apps kwrite unixodbc
libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp
python-mediaprof........
Aug 25 16:43:24 evohostingtor postfix/master[19471]: fatal: /etc/postfix/master.cf: line 24: field "unprivileged": bad value: "???"
Solution: I had the wrong thick dashes when c&ping (just retype them with your keyboard)
Aug 25 16:47:10 mailbox postfix/master[24498]: fatal: /etc/postfix/master.cf: line 25: bad transport type: syslog_name=postfix/auth-cleanup
auth-cleanup unix n - - - 0 cleanup
#-o syslog_name=postfix/........
The most common solution is to use the /etc/postfix/header_checks but this is a big problem.
Why is header_checks a problem? Because it does it to all mail whether incoming or outgoing and whether authenticated or not. We of course want as much header information for incoming as we can get for many reasons but many organizations want to secure and make their mail clients as secure as possible.
I adapted this solution to the client's custom config, they are configur........
CPanel says you can access 98% of the functions through CLI which experienced Unix/Linux admins prefer for simplicity and for scripting. I've never found CPanel easy to use from the admin panel, it seems everything is hard to find and a simple task becomes a series of hunts.
So for people like me here's the list: http://cpanel.net/system-administrators/command-line-scrip........
date -d @timestampgoeshere +%c
It's very handy and simple as shown above.........
The first is a dual CPU AMD Opteron 2373EE (4 cores x 2) and I think it did bad because it has some old 250GB SATAs which can only do about 65MB/s max sequential reads. I think it should have blown away the second (AMD X4 640 Quad Core).
[root@fs12home unixbench-4.1.0-wht-2]# ./Run
make all
make[1]: Entering directory `/root/unixbench-4.1.0-wht-2'
Checking distribution of files
./pgms exists
./src exists........
Bash weird variable whitespace missing
var=`cat tlds.csv|grep .ca,`
# echo "var=:$var:"
:ar=:.ca,Canada
Why is the v missing in the last line?
It should be
:var=:.ca,Canada
instead of
:ar=:.ca,Canada
I noticed a problem with the file with doing a "cat -v" on it.
Here's the issue, the file contains carat M ^M:
.vg,British Virgin Island........
Client Log
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to 192.168.1.253 [192.168.1.253] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: identity file /root/.ssh/identity type -1
debug1: identity file /root/.ssh/id_rsa type 1
debug1: identity file /root/.ssh/id_d........
Step #1 - Create Wrapper Script
vi /usr/local/bin/phpsendmail
#!/usr/bin/php
........
I really am a Linux fan but my comments here may not show it. Although I'm quite familiar with Linux CLI to administer servers, I find Linux GUI OS's like Ubuntu at times very clunky.
This is partially because there's no such thing as a "self-made" Linux from scratch where the UIwas designed by a single team. Linux is made up of several different projects that are generally completely separate and this lack of integratiion is a key issue that makes things f........
It really is as simple as:
cdrecord -v dev=/dev/sr0 pathtoyourisoimage.iso
-v is for verbose, I prefer it but if you don't you won't see as much output like below (I like to know the details and exactly what's happening)
dev=/dev/sr0 specifies the device name of your burner (they say not to use it and to specify some weird annoying device string but using the raw /dev has always worked for me and is how it should have been implemented from the start IMHO)........
carat M isn't this symbol ^ that you think, it can only be produced by typing "Ctrl-v, Ctrl-m". That you might see in text files saved from Windows.
tofrodos is the package that has dos2unix which is basically the same scripts that replace ^M with /n
tofrodos is the Debian/Buntu package name which has the dos2unix and unix2dos binaries........
netstat is weak and can't show udp connections and most other protocols, use "ss" which is what netstat should have been:
The "-u" switch stands for udp, here's a list of other options:
Usage: ss [ OPTIONS ]
ss [ OPTIONS ] [ FILTER ]
-h, --help this message
-V, --version output ver........
Centos 5 Postfix and SPAMASSASSIN Tutorial
yum install spamassassin
chkconfig spamassassin on
vi /etc/mail/spamassassin/local.cf
##############
#required_hits 5
#report_safe 0
#rewrite_header Subject [SPAM]
#5 is the least restrictive (means only the most obvious SPAM is caught. 0 is obviously the most restrictive/sensitive and would have lots of false positives
require........
Use "ImageMagick" which can be installed easily on most UNIX/Linux distros.
Remember that it will go with the standard file listing to determine the order but I believe you can manually specify multiple jpg's in the arguments.
Convert image/jpg to PDF
convert *.jpg yourpdf.pdf
This is a very handy and free tool.
Convert DOC/TXT documents to PDF
If you wanted to convert a .doc file or text........
This function and others may not work with the stock PHPinstall on Centos/CPanel: Fatal error: Call to > undefined function imagecreatefromjpeg()
Even with libjpeg-devel installed it won't work because PHP was not compiled with jpeg support, so we have to do the dirty work ourselves :)
Here is the command/yum's I did to install missing libraries for PHP that configure will complain about (yes it is a one by one process).
yum install bzip2-........
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........
I'm not a fan of Asus and won't be buying another because of having to fight Asus over a bogus warranty denial (it's a long story but they only replied about how to RMA my unit weeks later on the EXACT day the warranty expired).
Anyway, it's just a matter of hitting F9 to do this, there's no need to worry about booting from USB or CD (unless of course you want a different OS eg. Windows XP Pro, Vista/7, or a flavor of Linux or Unix). Also remember that you need to fully/properl........
The binary "iostat" comes from the package "sysstat" and is available on all Linux/Unix like platforms.
Use the "-m" option to give you what you probably want, which is to see in MB/s how much bandwidth each disk is doing.
iostat -m
Linux 2.6.24.2 ((none)) 04/16/10
avg-cpu: %user %nice %system %iowait %steal %idle
........
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........
Codelite is a great choice and I intend on getting back into C++ development and I think Codelite is great being cross platform.
It looks like it was designed with a lot of thought and should do the job better. I really dislike the bloated and confusing IDE's from big companies like Microsoft where you usually have to use .NET and other useless technologies that just give Microsoft the advantage over you, the programmer, and the users.........
Here are the results, it is Sempron 3000+ AMD Mobile, 500Gig HDD, 512MB RAM with shared ATI Radeon graphics.
# # # # # # # ##### ###### # # #### # #
# # ## # # # #&nb........
PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist:
[code:1:1fd0f3abbe]
if (!file_exists($OPENSSL)) {
//echo "ERROR: OPENSSL $OPENSSL not foundn";
}[/code:1:1fd0f3abbe]
I don't get itI can clearly see the contents of /usr/bin by using the PHP system fu........
SSH Public Key Authentication (Login Without Passwords)I've gone over this before but just a quick note!
the "authorized_keys" file in ~/.ssh
must be chmodded to "600" or public key authentication won't work.
I guess it's kind of a security/failsafe feature that I've
seen on all Linux and Unix OS's........
Linux Unix Xorg X Server Intel Extreme i810 Graphics Problem(EE) I810(0): No Video BIOS modes for chosen depth.
(EE) Screen(s) found, but none have a usable configuration.
I have a new Dell PC with one of the latest Intel Extreme Graphics on-board crap. From what I can see any Linux/Unix/FreeBSD versions running XFree86 or Xorg from years ago or the latest version today will have this problem.
It's easily corrected FOR MOST people. Go into your........
Xorg fonts missing Xorg.0.logThis happened on a PCBSD installation but it could happen on any Unix/Linux Xorg installation:
If the text on your screen is too small and you're running at a high resolution if you do a
[code:1:04ca0d3455]cat /var/log/Xorg.0.log | more
[/code:1:04ca0d3455]
You'll see a bunch of fonts missing, specifically the 75dpi and 100dpi ones that you really need :)
(WW) The directory "/usr/X11........
BMP is the best FreeBSD/Unix MP3 player I can findSeems like a better written XMMS that uses Winamp skins
http://www.sosdg.org/~larne/w/BMP_Homepage........
Mounting NTFS in UnixJust a quick tutorial to mount your NTFS volumes in Unix (FreeBSD/Linux)
[quote:4a9de7bf80]mount -t ntfs -o umask=0 /dev/your_partition /mnt/your_mount_point[/quote:4a9de7bf80]
[b:4a9de7bf80]-o umask=0[/b:4a9de7bf80] is to ensure all users can access the mounted partition (otherwise don't use it and only root can access the mounted partition)
[b:4a9de7bf80]-t ntfs[/b:4a9de7bf80] is simple because it just lets mount kno........
Bash Script Infohttp://www.faqs.org/docs/Linux-HOWTO/Bash-Prog-Intro-HOWTO.html#ss10.5
http://www.scit.wlv.ac.uk/~jphb/spos/notes/shell/shell5.html
http://quong.best.vwh.net/shellin20/#LtohTOCentry-41
http://www.cactus.org/~dak/shellscript.html
http://db.ilug-bom.org.in/Documentation/abs-guide/
http://pegasus.rutgers.edu/~elflord/unix/bash-tute.html
http://heather.cs.ucdavis.edu/~matloff/UnixAndC/Unix/CShellII.html
Since bash i........
Basic Port ListingHopefully someone finds this useful or at least interesting.
http://www.sans.org/top20/#u9
Name Port Protocol Description
Small services ........
gnuCash is available for all main platforms, Linux/Unix, MacOS (FreeBSD anyway), and Windows.
You can download gnuCash free from here.
It does seem to be fairly full featured and somewhat straight forward, but like so many programs it is missing a few key features or things don't work quite right.
It doesn't support importation of CSV files, which is a big minus. And the developers rather than wanting to add support have just dec........
The "Geoip" package is available on virtually all Linux and Unix like systems and is very handy in looking an IP address' corresponding country.
The homepage of the maintainers is here.
They also have a package called "Geocity" which can be downloaded from their site, it is still free and gives you a close indication of the city the visitor is from. You can........
Shortcut/Easiest Way To Create A Self-Signed Key:
openssl req -new -x509 -nodes -days 1530 -out server.crt -keyout server.key
Using the above, you instantly create a self-signed certificate valid for 1530 days and you can simply skip to step #5.) below.
If You Need a Real SSLCertificate (eg. Equifax/Openssl) then you need to create a CSR request (you'll need to follow Steps 1.) and 2.) in order to create the CSR. You then upload the CSR Certi........
The results are still not flattering and are nothing close to native performance. Unless GlusterFS has a "DRBD-like" option to delay writes over the network and to only read from the client side, I don't see how performance can ever improve much more.
After doing some client optimizations Iadded more to the score:
Start Benchmark Run: Sun Nov 29 00:37:44 PST 2009
00:37:44 up 3 min, 1 user, load average: 0.01........
You might remember my original GluserFS/OpenVZ benchmark which produced a horrible 29.8
This is the exact same system, but using the latest 2.0.8 (with some small files patch which speeds up performance) you can see it is about 25% faster.
I also haven't tuned my config files at all, but there are some settings that should increase performance on small files which I believe i........
This is very disappointing since GlusterFS markets itself as a solution to deploy VPS servers on. On the HNitself I get a Unixbench of about 360.
I'm also using an SSH tunnel to secure the communications, but even before that, things seemed very slow.
# # # # # # # #####&n........
In those 4 simple commands you can setup mutual key exchange between two sshservers by using a single login shell session and single window.
*Just change the IP address examples of (10.10.0.2) to the target of your mutual key exchange. It doesn't matter if the server is on a LANor WAN(well unless the server is behind a firewall and you cannot SSHinto it).........
In Newer Linux Distros This Way Is Easiest and works on newer versions like Ubuntu, Mint, Fedora, Centos, Debian etc.
#if you are missing timedatectl this in newer distros like Ubuntu/Mint/Debian and are using a container like Docker then do "apt install systemd"
timedatectl set-timezone America/Vancouver
Replace the America/Vancouver with the correct timezone.
To see the list you can just type "timedatectl set........
It's actually very simple and "grep" makes it as easy as possible. I'll outline a few common scenarios and provide some examples.
Say you want to search ALLfiles within the current directory (and inside/deeper) for the text "phpinfo()"
grep -R "phpinfo()" *
If you want to search only certain files such as only .txt you would do this instead:
grep -R "phpinfo()" *.txt
As you ca........
There is a tool called "xml2" which will parse both HTML and XML scripts, this is very useful to do a mass extraction or conversion of data based on say an HTML table etc..
It becomes even more powerful using bash if certain tags are identified with a certain class="" attribute or something else unique to only the tags you want.
Happy parsing.........
Truly, the only way to unleash the capabilities and customization abilities of iPhone are to jailbreak, it's not just for hackers anymore.
A few days ago someone by the named of "geohot" released a single click application called "purplera1n", which does the entire operation smoothly and seamlessly.
In our case, the first time it went as far as "done, wait for reboot" on our Windows machine and for minutes we waited and saw the pic on the iPhone w........
As much of a computer nerd as Iam, I'm usually a late adopter to technology for a few reasons. Ifeel most new hyped technologies and electronics are mainly fads, and I'm also cheap.
Adopting later means you avoid the bugs, kinks and most importantly pay the lowest price, that's me being cheap again :)
I never read much about the iPhone but Isaw all the hype around it and until recently I wasn't a big fan of anything Apple until a few years ago I realize........
Server not using user level security and no password supplied.
tree connect failed: NT_STATUS_WRONG_PASSWORD
That happens when trying to use smbclient to connect to a share. The weird thing is that I can authnenticate just fine from Windows XP.
It is partially my mistake, I forgot this share does have a password. I've tried authenticating with the correct user and also with "Guest" because this works in Windows. In Linux I ........
This will give you the basic info needed to browse and connect to Samba shares from the command line. From the GUI of Gnome or KDE etc, it is pretty standard and straight forward. However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go.
First get a list of all the Samba/SMB shares on the target.
smbclient -L hostname........
There's a lot of outdated information and confusion for system administrator's out there.
One annoying task for many an Administrator has been backing up data in Linux. You don't need any GUI tools such as K3B or GnomeBaker. Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle.
At a later date we'll cover how scripting can automatically backup certain........