/ - rtt - IT Resource

  • 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 I always 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........
  • HP DL385 G7 Linux BIOS Update Flash


    wget https://downloads.linux.hpe.com/repo/spp/rhel/6/x86_64/current/CP017004.scexe --2018-08-16 05:11:16--  https://downloads.linux.hpe.com/repo/spp/rhel/6/x86_64/current/CP017004.scexe Resolving downloads.linux.hpe.com (downloads.linux.hpe.com)... 15.249.152.85 Connecting to downloads.linux.hpe.com (downloads.linux.hpe.com)|15.249.152.85|:443... connected. HTTP request sent, awaiting response... 200 OK Length: 1525561 (1.5........
  • 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........
  • OpenVPN auth-user-pass-verify ENV script error


    Starting with newer versions of OpenVPN I believe 2.2+ you need to have "script-security 3" set or you can't execute a third party script. Prior to that you could also use the auth-user-pass-verify like this: auth-user-pass-verify ./validate.pl "$username $password $ip" via-env Options error: the --auth-user-pass-verify directive should have at most 2 parameters.  To pass a list of arguments as one of the paramete........
  • Cannot create gradle for conversations


    The main issue is it looks like Java is not configured to accept the invalid ssl cert that is coming from the download location. Exception in thread "main" java.lang.RuntimeException: javax.net.ssl.SSLException: java.security.ProviderException: java.security.InvalidKeyException: EC parameters error  export ANDROID_HOME=/home/user/Downloads/tools/ Conversations-master$ ./gradlew Downloading https://services.gradle.org/distributions/grad........
  • not allowed to execute '/usr/bin/apt-get install eclipse' as root linux sudo user permisson issue and solution


    This is most likely to happen on a normal GUI system like Ubuntu or Linux Mint.  If you or the user is meant to have sudo / root privileges it is as simple as editing the following files: Now assume your username is "iamtheuser" vi /etc/group adm:x:4:syslog,iamtheuser sudo:x:27:anotheruser,iamtheuser Find the above lines and add a comma and "ia........
  • Intel NUC J3455 Linux Kernel freeze slowness 4.4.98 errors


    It looks like this has something to do with APIC but I am not sure.  I have similar CPUs with a different MB and BIOS that work fine on the same type of kernel.  A lot of time the issue is because of the C-step setting in the BIOS. The same thing happened on the 2.6 kernel with Centos 6 but this is a homebrew 4.4 kernel so I am not sure why it is happening when even Centos 7 (3.2) kernel works OK. Solution - It comes down to the BIOS set........
  • IcedTea Java Web Viewer Config Utility How To Enter


    In at least Ubuntu and Mint there is nothing intuitive about configuring Java. Execute it to get to it: itweb-settings You'll be able to configure different options and variables.   You can also check under Security as some of those settings could prevent applets from starting or prompting to........
  • linux cp and mv will not overwrite due to alias!


    This through me for a loop when I would do a cp -rf or mv -f nothing would get overwritten even if piping y or yes to the command. Type alias and you'll see why: alias cp='cp -i' alias l.='ls -d .* --color=auto' alias ll='ls -l --color=auto' alias ls='ls --color=auto' alias mv='mv -i' alias rm='rm -i' The -i is a safeguard against messing things up but however does mess things up worse when you know what........
  • rsync run as root sudo without password


    This is a common issue, what if a issue shouldn't have root but you want to use that user to make a full backup of a system?  They of course need root access. You can actually just give them passwordless sudo access to rsync in /etc/sudoers: sudo vi /etc/sudoers yourusername ALL = NOPASSWD: /usr/bin/rsync   Here is how you would execute rsync: The key thing for the remote host is to........
  • Coolermaster CM Storm Enable LED Backlight in Fedora/Ubuntu/Mint Linux Howto - MB24 Keyboard and MS2K Mouse


    Just type the following in the bash/terminal shell to enable the blue LED light on the Coolermaster CM Storm keyboard: xset led 3 To make it automatic and permanent execute the following as root: echo "xset led 3" >> /etc/rc.local   This is a fairly nice gaming keyboard which I bought because I type very quickly and the cheap standard keyboards simply can't keep up!........
  • How to Execute PHP in .html files with Apache in Linux Centos/Debian/Ubuntu etc


    Add this to the .htaccess file #right/working: AddType application/x-httpd-php .html .htm   #wrong (won't work in many cases): AddHandler application/x-httpd-php5 .html .htm........
  • forcedeth MCP55 Nforce3600 Nvidia Network NIC Card Not working in Linux at 1gigabit speeds


    Now many people report this card simply not working in various Linux distros and kernels.  My issue is different, it always works at 100mbit (eg. plugged into a 100mbit switch) but no matter what 1000M/gigabit switch I would try, it would never work. The link would be up (the lights were on) and the OS detected the link as being up as well but it wouldn't work at all and could not pass data in or out (not even a ack/ping). There is one simple solution and command........
  • SAS2008 LSI 9200-E Linux Upgrade Flash Firmware with sas2flash


    Download from here http://www.avagotech.com/products/server-storage/host-bus-adapters/sas-9200-8e#downloads   sudo Installer_P20_for_Linux/sas2flash_linux_i686_x86-64_rel/sas2flash -listall LSI Corporation SAS2 Flash Utility Version 20.00.00.00 (2014.09.18) Copyright (c) 2008-2014 LSI Corporation. All rights reserved   &nbs........
  • Avocent 8020 KVM Java Icedtea Viewer


    It seems every other updated version of Java or Icedtea breaks things and I will save the frustration of Java for another post. *If you get the icedteaweb window but nothing loads or prompts it is probably your security settings that won't even prompt to run it.   See this article to solve that problem. To fix this error you need to edit the java.security file m........
  • Centos/obfsproxy errors


    I never did get it working, it is too bad as obfsproxy should really be an option and integrated into the OpenVPN client and server or something similar:   yum -y install python-pip python-devel No package python-pip available. #install the EPEL repo python-pip install obfsproxy python-pip install obfsproxy -bash: python-pip: command not found pip install obfsproxy    &........
  • CPanel Link to all of the command line options


    <p>CPanel says you can access 98% of the functions through CLI which experienced Unix/Linux admins prefer for simplicity and for scripting.&nbsp; 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.</p> <p>So for people like me here's the list: <a href="http://cpanel.net/system-administrators/command-line-scripts/">http://cpanel.net/system-administrators/command-line-scrip........
  • Howto Execute PHP from within an HTML or other file with an htaccess file on Apache


    Add this to a new ".htaccess" file inside the directory where the .html resides: AddType application/x-httpd-php .php .html........
  • PHP Security - Enable Safe Mode to increase security


    Everyone should be running with safe_mode on in /etc/php.ini (on Centos) as it makes exploiting your system more difficult is PHP can't execute anything on the system if a script is exploited. For example with Safe_Mode on the only executable files on the system are ones in the safe_mode_exec_dir = /safephp This is crucial, if you must execute anything from PHP then you have to copy the binary and assign to the user that Apache runs your site under.&........
  • Execute Local Bash Scripts remotely by SSH


    for ip in `cat fixlist.txt`; do sudo -u apache ssh root@$ip "`cat iptablesrules.sh`" done In the above example we are going to execute the commands within the local file "iptablesrules.sh" on all the machines in "fixlist.txt".  This is a great way of performing server maintenance in a clustered or cloud environment.........
  • 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........
  • mysqldump: Couldn't execute 'show create table `general_log`': SHOW command denied to user 'user'@'localhost' for table 'general_log' (1142) - Solution


    mysqldump: Couldn't execute 'show create table `general_log`': SHOW command denied to user 'user'@'localhost' for table 'general_log' (1142) One of my clients almost found out the hard way, here is an unlikely situation that happened. 1.) Years ago the client had another VPS to which they backed up a BLOG nightly to an .sql file, what they forgot is that the file also contained all databases (they used the --all-databases option but forgot).  So imagi........
  • mysql how to execute script from the bash prompt .sql


    mysql -u username --password='yourpassword' < thesqlscript.sql........
  • Bad Hard Drive Slows Down Computer


    Here's a proven example of what a bad hard drive can do, it was technically functioning OK in 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 1TB Hitachi 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 log all PHP based E-mails for abuse


    Step #1 - Create Wrapper Script vi /usr/local/bin/phpsendmail #!/usr/bin/php <?php //changed by realtechtalk.com to make the log readable /**   This script is a sendmail wrapper for php to log calls of the php mail() function.   Author: Till Brehm, www.ispconfig.org   (Hopefully) secured by David Goodwin <david @ _palepurple_.co.uk> */........
  • Thunderbird How-To Copy/Backup/Restore Accounts and Settings to Another Computer


    The best way is to use rsync, I've set it up so it doesn't copy unnecessary files, or at least ones I'm sure aren't needed. Here is the rsync command I used (adapt to your specific Thunderbird profile location): rsync -hazv user@remotehost.com:/home/user/.thunderbird/sbrer.default/* /home/user/.thunderbird/4nyb0.default/ --exclude=global* --exclude=Cache --exclude=ImapMail --exclude=Mail This is a great way to get your e-mail accounts going on a new c........
  • 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........
  • vnstat setup guide/tutorial


    yum -y install vnstat chown nobody.nobody -R /var/lib/vnstat/ #replace venet0 below with your desired interface sudo -u nobody vnstat -u -i venet0 #edit: vi /etc/sysconfig/vnstat #VNSTAT_OPTIONS="-i venet0" # only use the sed below if you are using venet0 instead of eth0 or replace accordingly sed -i 's/eth0/venet0/g' /etc/sysconfig/vnstat   [root@monitor]# yum install vn........
  • SMARTCTL additional SMART command testing using short and long tests


    smartctl -t long /dev/sda (note you can specify short, but it's not as thorough as long of course). smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF OFFLINE IMMEDIATE AND SELF-TEST SECTION === Sending command: "Execute SMART Extended self-test routine immediately in off-line mode". Drive command "Execute SMART Extended sel........
  • ls: error while loading shared libraries: libtermcap.so.2: cannot open shared object file: No such file or directory solution


    ls ls: error while loading shared libraries: libtermcap.so.2: cannot open shared object file: No such file or directory This is not an ldd problem or case of anything missing, this only happened after I upraded Ubuntu. declare -x PATH="/home/user/bin:/usr/local/bin:/usr/bin:/bin:/usr/games" "/home/user/bin" is the problem!  It's weird because I have no idea how it happened.........
  • Failed to save enabled features : The Suexec command on your system is configured to only run scripts under /var/www, but the Virtualmin base directory is /home. CGI and PHP scripts run as domain owners will not be executed.


    Apache/httpd Failed to save enabled features : The Suexec command on your system is configured to only run scripts under /var/www, but the Virtualmin base directory is /home. CGI and PHP scripts run as domain owners will not be executed. This is because I never edited the Apache Config and Virtualmin config to reflect my new/current updated structure.........
  • 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........
  • HeartBeat Error/High Load heartbeat: [7120]: WARN: Gmain_timeout_dispatch: Dispatch function for retransmit request took too long to execute: 20 ms (> 10 ms) (GSource: 0x926b390)


    My LOG is flooded with those messages many times per second. I don't know what is wrong with heartbeat, but restarting the service fixed it.........
  • Installing Virtualbox on Centos 5.5


    wget http://download.virtualbox.org/virtualbox/3.2.8/VirtualBox-3.2-3.2.8_64453_rhel5-1.i386.rpm rpm -i http://download.virtualbox.org/virtualbox/3.2.8/VirtualBox-3.2-3.2.8_64453_rhel5-1.i386.rpm error: Failed dependencies:     libGLU.so.1 is needed by VirtualBox-3.2-3.2.8_64453_rhel5-1.i386     libSDL-1.2.so.0 is needed by VirtualBox-3.2-3.2.8_64453_rhel5-1.i386     libXmu.so.6 is needed b........
  • crontab Reference/How To/Info/Guide


    I can never actually remember the order and the number of parameters so here they are: minute hour day of month month day of week command 0 5 *........
  • 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........
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