• Docker Tutorial HowTo Install Docker, Use and Create Docker Container Images Clustering Swarm Mode Monitoring Service Hosting Provider


    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.........
  • Wordpress How To Add Featured Image To Post in Hueman Theme


    It is different than other Wordpress templates. You have to edit the following file: wp-content/themes/hueman/parts/single-heading.php Add the following PHPcode to the bottom: ........
  • How To Replace Audio Track of Video using ffmpeg


    A very common use case is that you don't want to waste time using a video editor that requires you to open it up and manually import the video clip and audio clip, then manually delete the old audio track and import the video and new audio. That's too much work and time since we don't want to go through the hassle. ffmpeg is our solution, all we have to do is specify 3 variables and we're done! -i Windows2019-Server-Noaudio.mp4 is our in........
  • QEMU-KVM KVM Command Line Practical Guide


    Iam going to build this based on a series of small posts I've made as I feel much of the information is actually hard to find and piece together from the rest of the web. What I'm going to focus on is how to use virtio as the NIC because if you don't you get very slow NIC speeds but with the virtio NIC model you basically get host speeds. /usr/libexec/qemu-kvm -enable-kvm -smp 8 -m 16000 -net user -net nic,model=virtio -drive file=ubuntu-gpt2large.img,if=virtio........
  • Debian Ubuntu and Linux Mint Broken Kernel After Date - New Extra Module Naming Convention


    I don't consider a lot of these "extra" kernel modules "nice to have" as they often contain drivers for essential items like your soundcard, your NIC and many other devices that may not work. Sometimes you may find that "sound" or "ethernet" worked before a kernel/OS upgrade and now in the new version they don't. Often it will be because you need to install the "extra" kernel modules. One other weird thing is that sometimes........
  • Cisco Unified Communications Manager / CUCM IP 8.6,10,12 Install Error Solution


    Install Errors on Version 12: This error happened on QEMU emulator version 2.11.1 pve-qemu-kvm_2.11.1-5 on Proxmox/Debian but installing on QEMU.12 on Centos 6 did not produce the error. *Update it is not related to the OS or QEMU version. This happened in Centos 6 too after a second install. What really causes this even though you successfully install........
  • Cisco Unified Communications Manager 12 Install Errors on Proxmox/KVM


    The strange thing is that usually the first install or two will work on any new machine but then it suddenly won't. I had this experience on QEMU 2.13 on a different machine. There is something finicky or buggy about the CUCM installer even when choosing the same virtual hardware specs. qemu-kvm command: /usr/libexec/qemu-kvm -version QEMU PC emulator version 0.12.1 (qemu-kvm-0.12.1.2-2.506.el6_10.1), Copyright (c) 2003-2008 Fabrice Bellard ........
  • iptables linux firewall recommended rules for public computing


    Whether you are at work, at the coffee shop or on the public internet here are some basic but effective rules for iptables that lock things down (eg. no one can SMB or SSH to you or really anything): # Generated by iptables-save v1.4.21 on Fri Dec 14 14:00:08 2018 *nat :PREROUTING ACCEPT [160:19844] :INPUT ACCEPT [4:357] :OUTPUT ACCEPT [2955:182236] :POSTROUTING ACCEPT [2955:182236] COMMIT # Completed on Fri Dec 14........
  • PHP Issues With Decoding Strange Smart Quotes And Non-Standard ASCII Characters


    When using strip_tags and html_entity_decode with PHPit often breaks and produces annoying diamonds with question marks. It is probably because of characters like these: … (looks like 3 dots but it is a single weird character). ’ (looks like a normal apostraphe but it is not) ” (looks like a normal double quote but it is not). An easy way to sort this out is to copy the above and search in an ASCII table to extend the functional........
  • Adobe Acrobat Reader for Linux to use and view XFA Fillable Forms


    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........
  • gmail.com address failing in Postfix


    Aug 10 01:11:54 mailserver postfix/smtp[6180]: 020AE17C2BD1: to=, relay=none, delay=0.29, delays=0.28/0/0/0, dsn=5.4.4, status=bounced (Host or domain name not found. Name service error for name=gmail.con type=A: Host not found) A user complained that their e-mails weren't being delivered but they actually made a small typo and used gmail.con so it wasn't working as expected of course........
  • Postfix How To Change Sending IP Address To Specific IP Binding or Interface


    Ithought I'd post this becuase there is some bad information out there. Some guides tell you to edit /etc/postfix/master.cf (-o smtp_bind_address=) but this doesn't work. The same guide also says if you don't change it there you end up changing the listening IP/bind interface which is also not true. Here is a simple and effective way to change Postfix's sending/binding/outgoing IP address (very important for reverse DNS and so mail servers don't block you)........
  • postfix errors fatal: no SASL authentication mechanisms /usr/libexec/postfix/smtpd: bad command startup -- throttling solution


    Jul 3 22:12:17mailserver postfix/smtpd[6195]: fatal: no SASL authentication mechanisms Jul 3 22:12:18mailserver postfix/master[4881]: warning: process /usr/libexec/postfix/smtpd pid 6195 exit status 1 Jul 3 22:12:18mailserver postfix/master[4881]: warning: /usr/libexec/postfix/smtpd: bad command startup -- throttling This only ever happens in my experience when the authentication method is actually Dovecot. Usually the problem........
  • 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..........
  • "Object of class WP_Term could not be converted to string"


    Normally when I've seen this it's when you are using a variable like a normal string when in fact it's actually an array such as this example: [Tue Mar 13 04:22:35 2018] [error] PHP Catchable fatal error: Object of class WP_Term could not be converted to string in /vhost/httpdocs/wp-content/plugins/wp-instagram-post/classes/class-woo-igp.php on line 578 &nbs........
  • Wordpress Instagram Post Modify Plugin To Add Tags


    I modified this code after quickly learning how Wordpress plugins actually work, how they're called etc.. was the first trick to modifying the code to add tags. Add this code after line 570 in wp-content/plugins/wp-instagram-post/classes/class-woo-igp.php &nb........
  • ffmpeg trouble concatenating similar but different files


    When things go wrong your video is basically unplayable or the first video plays fine and then freezes when moving on to the next. Generally if both videos weren't produced with the exact 100% same settings you will have issues. You can try the basic concat but it often won't work right. Solution for me: My example uses 3 videos in total so "n=3" and a=1 to include audio. ffmpeg -threads 12 -i file1.mp4 -........
  • 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 ........
  • phpBB3 slow and internal dummy connection


    Using Apache 2.2 and PHP5.6 PHPBB3 is very slow to respond. Actually for some reason it takes so long to even register a log entry in access_log as in several seconds or a few minutes later it shows up in Apache. All other vhosts and Apache access stops working and freezes until the request to access PHPBB3 slowly completes. It seems to randomly be slow if you stop using it whether for posting or reading the forums. I've migrated to different machines including........
  • iptables how to forward localhost port to remote public IP


    iptables -t nat -A OUTPUT -m addrtype --src-type LOCAL --dst-type LOCAL -p tcp --dport 3306 -j DNAT --to-destination ip.ip.ip.ip iptables -t nat -A POSTROUTING -m addrtype --src-type LOCAL --dst-type UNICAST -j MASQUERADE sysctl -w net.ipv4.conf.all.route_localnet=1 Make sure you substitute "ip.ip.ip.ip" for your real public IP and also the "--dport 3306" for the port you want to forward. Finally run the sysctl command and........
  • MySQL PHP adding a backslash/escaping apostrophes Solution


    The first thing to diagnose is what is actually in the database (use PHPMyAdmin or CLI). You will of course either find that the backslash is either in the database or not. If the backslash is in the database you probably have magic quotes gpc/runtime on and/or are calling the "addslashes()" function which does this. If you are escaping your data with mysql_real_escape_string() then think again, you probably have magic quotes gpc enabled either in php.ini or........
  • Installing zoneminder on Ubuntu/Debian Linux Howto


    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........
  • Centos OpenDKIM & Postfix Setup Guidel


    #from epel repo yum -y install opendkim chkconfig opendkim on cd /etc/opendkim/keys opendkim-genkey -vd mail.server.com opendkim-genkey: generating private key opendkim-genkey: private key written to default.private opendkim-genkey: extracting public key opendkim-genkey: DNS TXT record written to default.txt ........
  • Lost connection to MySQL server during query [2013]


    This happened while trying to delete several thousand users from phpBB and basically corrupted the innoDB tables. InnoDB: Page lsn 3 881164362, low 4 bytes of lsn at page end 881164362 InnoDB: Page number (if stored to page already) 86920, InnoDB: space id (if created with >= MySQL-4.1.1 and stored already) 0 InnoDB: Page may be an index page where index id is 700 InnoDB: (index "tid_post_time" of table "phpBBdb2005"."phpbb3_p........
  • Postfix Errors & Solutions "unprivileged": bad value: "???" - bad transport type:


    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/........
  • Postfix how to secure outgoing authenticated e-mails for privacy and hide the IP address, mailer and other things


    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........
  • 2CO/2Checkout Howto Enable IPN/Notification Setup & Script Info


    https://www.2checkout.com/documentation/notifications/order-created It shows all the parameters that get passed so you can make a simple script to process it. To enable 2CONotifications you need to do the following: Login Browse to the top right to an icon that looks like a "circle with horizontal lines inside" - Notifications. Enter the appropriate URL for your IPN/Notification processing script (........
  • The Best NoSQL Solution


    To first start off, there are many misconceptions about NoSQL and especially its strengths and weaknesses. Even the popular NoSQL solution MongoDB is fraught with issues that no one seems to be concerned about aside from a few but there are serious issues with database integrity and verified writes. MySQL was considered dangerous or incomplete at one point without having the transactional safety features of Oracle for example. However the NoSQLimplementations seem........
  • 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........
  • 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........
  • iptables redirect ports to a different host and port + NAT Masquerade howto/solution


    This is important if you need public access to internal IPs such as at your office and don't want to use a VPN just to SSHinto different servers: Below forwards the port "10001" to the IP192.200.5.53 on port 22 (of course adjust it to your needs). iptables -t nat -A PREROUTING -p tcp --dport 10001 -j DNAT --to-destination 192.200.5.53:22 Remember to enable MASQUERADE on your NAT IPs or they won't be able to talk to the outside world (........
  • PHP How To Create and Assign Variables from POST/Submit FORM


    foreach ($_POST as $key => $value) { if ( $key != submit ) { $values.="$key=$value<........
  • postfix/dovecot Sent emails missing sometimes


    On occassion and from a variety of networks and clients, Sent messages don't get saved. I'm wondering if these log messages could be why: May 3 14:16:39 mail.box postfix/smtpd[5195]: connect from 192.168.1.58 May 3 14:16:39 mail.box postfix/smtpd[5195]: SSL_accept error from 192.168.1.58: -1 May 3 14:16:39 mail.box postfix/smtpd[5195]: lost connection after CONNECT from 192.168.1.58 May 3 14:16:39 mail.box postfix/smtpd[5195]:........
  • mdadm recover from dead drive


    mdadm --manage /dev/md3 --add /dev/sda1 cat /proc/mdstat Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10] md0 : inactive sdd2[1] sdd1[2](S) 31270272 blocks md3 : active raid1 sda1[2] sdb1[1] sdc1[3](F) 943730240 blocks [2/1] [_U] [>....................]........
  • Setup PXE Boot using Centos and dhcpd, tftp and syslinux


    This is something I often setup for clients because it's very helpful for people in datacenters, this allows custom OS installs on demand, you can customize it more by using kickstart etc.. but here's a base I use before customizing more: This little script below will install everything you need to get booting by PXE Linux. It also assumes you set a local IP (be sure not to overwrite your existing IP) on eth0:0 (note the :0) as 192.168.1.10 and it........
  • postfix how to send to multiple recipients default limit of 1000


    The size of the message you are trying to send exceeds a temporary size limit of the server. The message was not sent; try to reduce the message size or wait some time and try again. The server responded: 4.5.3 Error: too many recipients. We set this in main.cf: smtpd_client_recipient_rate_limit=0 We didn't specify it before and the default is said to be 0/unlimited and it still didn't change anything.........
  • failed to IDENTIFY (INIT_DEV_PARAMS failed, err_mask=0x80)


    [ 12.460014] ata1: SRST failed (errno=-16) [ 17.626677] ata1: link is slow to respond, please be patient (ready=0) [ 22.480011] ata1: SRST failed (errno=-16) [ 27.646681] ata1: link is slow to respond, please be patient (ready=0) [ 38.106817] ata1.01: failed to IDENTIFY (INIT_DEV_PARAMS failed, err_mask=0x80) [ 48.266676] ata1: link is slow to respond, please be patient (ready=0)........
  • OpenVPN don't use bridgestart.sh or bridge at all use iptables


    I used the suggested script to bridge from OpenVPN and it took my client's server off-line! Don't ever use their "sample" scripts if you don't have another way of accessing the server than SSH. I actually found it easier to use iptables to tell it to route IPs based on a certain subnet to route through eth0: iptables -t nat -A POSTROUTING -s 192.168.200.0/24 -o eth0 -j MASQUERADE Replace "192.168.200.0/24" with your subnet of cour........
  • postfix lopback error solution


    This is the mail system at host mail.postmail.com. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to If you do so, please include this problem report. You can delete your own text from the attached returned message. &........
  • VPS Server Scam/Review/Complaint List


    These are the only two I've encountered but here is the low-end and note my story is not at all unique. In my case I was scammed out of money and did not receive any service at all from either company. Santrex Review/Scam/Complaint Santrex never provided any working server, I believe it was just a dummy management Solus server because the server said it was booted but never connected to the console. I complained to them and eventually the support adm........
  • Enable SPAMASSASSIN on Postfix in 5 minutes


    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........
  • Postfix header_checks using regexp and multiple lines


    I'm posting this because it wasn't easy or obvious how this would be accomplished and the man page leaves it to guesswork. Multi-line body_checks Example 1 /........
  • 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........
  • Postfix/Any Email Server check for Open Relay


    The first thing you need to remember is not to check from the same host/server itself. This is a silly mistake I made, the reason is that many mailservers and especially postfix are configured to allow relaying from the localhost/same host. If you do that you'll get a false positive. *Make sure you test from another host/system than the mail server itself! telnet yourmailserverhost.com 25 220 Courier (FreeBS........
  • email server messsages rejected without reverse DNS DNS check failure Client host rejected: cannot find your reverse hostname Cannot resolve PTR record


    Basically you should always be 100% sure that whatever IPyour mail server sends out with has reverse DNS/PTR records. Remember that unless you own your IPs then you won't be able to set your own reverse DNS. Even if you were to create a reverse PTR record on your DNS servers it will be ignored. Reverse DNS is queried to pre-assigned DNS servers of your ISP, so therefore you'll need to contact your ISP/Colo/Hosting provider to do a reverse DNS entry. If you don't have........
  • Postfix Enable SSL/TLS with your certificate


    Create Cert & Key: openssl req -new -x509 -nodes -days 1530 -out server.crt -keyout server.key mkdir /etc/mailssl chmod 700 /etc/mailssl cp server.* /etc/mailssl Postfix SSL config Edit /etc/postfix/main.cf: #SSL stuff smtpd_tls_cert_file = /etc/mailssl/server.crt smtpd_tls_key_file = /etc/mailssl/server.key To make smtps w........
  • Understanding /etc/aliases from sendmail when using with postfix or other MTA's


    understanding /etc/aliases *remember to apply changes you need to run "newaliases" after editing /etc/aliases one thing I don't get is that it doesn't allow you to specify the whole e-mail address on the left-hand side eg: yourfullemail@domain.com: someotheremail@domain.com postalias: warning: /etc/aliases, line 109: name must be local (if you try the above) It works more like this: your........
  • Installing Webmin & Enabling SSL


    Webmin Setup Centos 5: wget http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html&ts=1294339690&use_mirror=surfnet [1] 24229 [2] 24230 [root@host ~]# --2011-01-06 21:48:20-- http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html Resolving downloads.sourceforge.net... 216.34.181.........
  • Virtualmin/Webmin Postfix Error: The status of your system is being checked to ensure that all enabled features are available, that the mail server is properly configured, and that quotas are active ..


    Virtualmin Postfix Error: The status of your system is being checked to ensure that all enabled features are available, that the mail server is properly configured, and that quotas are active .. A problem was found with your Postfix virtual maps : No map sources were found in the Postfix configuration .. your system is not ready for use by Virtualmin. ........
  • 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........
  • PHPBB Drop All Tables


    PHPBB Drop All TablesSQL Syntax: [quote:75acd496c1]drop table phpbb_auth_access, phpbb_banlist, phpbb_categories, phpbb_config, phpbb_confirm, phpbb_disallow, phpbb_forum_prune, phpbb_forums, phpbb_groups, phpbb_posts, phpbb_posts_text, phpbb_privmsgs, phpbb_privmsgs_text, phpbb_ranks, phpbb_search_results, phpbb_search_wordlist, phpbb_search_wordmatch, phpbb_sessions, phpbb_smilies, phpbb_themes, phpbb_themes_name, phpbb_topics, phpbb_topics_watch, phpbb_user_group, p........
  • 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........
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