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    This will be the goto to help solve e-mail delivery issues and talk about many practical issues that happen between developers, admins and scripts that send e-mail and do things that may not be acceptable or cause deliverability problems. Sendmail Stuff Edit /etc/mail/sendmail.mc The problem is that if you send directly out from the server using the mail function, the Return-path of the e-mails will be username@thehostnameoftheserver.com. Let........
  • Linux Ubuntu Mint how to check nameservers when /etc/resolv.conf disabled solution


    You'll notice that /etc/resolv.conf contains dire warners on most Linux Desktops. # This file is managed by man:systemd-resolved(8). Do not edit. # # This is a dynamic resolv.conf file for connecting local clients to the # internal DNS stub resolver of systemd-resolved. This file lists all # configured search domains. # # Run "resolvectl status" to see details about the uplink DNS servers # currently in use........
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    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.........
  • Juniper JunOS Command Overview and Howtos Switch, Router, Firewall Tutorial Guide


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  • Linux how to whois query other gTLDs such as .club solution


    whois in Linux is incredibly out of date and does not seem to recognize most new TLDs domains, but there is a quick and easy tip/hack/tweak for this. An example of new TLD's site as .review .site .club whois somesite.club No whois server is known for this kind of object. bash to the rescue Now I did try to apply this in .bashrc but DONOT! Ithink the * wil........
  • Location of cPanel apache access logs


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


    vi /etc/yum/pluginconf.d/fastestmirror.conf exclude=.hk,.cn You could also use specific domains but as you can see above we are blacklisting all Hong Kong and Chinese mirrors in this example.........
  • cPanel How to set SSL and Dedicated IP in cPanel


    Account Functions -> Change Site's IP Address Choose the domain and then click "Change" Choose the new IP 1.) Setup SSL Certificate in cPanel Click on "SSL/TLS Manager" under the "Security" section. 2.) Under " Private Keys (KEY)" Click "Generate, view, upload, or delete your private keys." Choose "Key Size: 4096........
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    CPanel ->Basic cPanel &WHMSetup At the bottom you'll see them, set the nameservers you want to use and the corresponding A record if needed. Then all new domains will use those settings/nameservers. It's strange that there's no section for this specifically.........
  • GoDaddy How To Register and Create/Use Your Own DNS Name Servers


    http://support.godaddy.com/help/article/668/registering-your-own-nameservershosts?pc_split_value=1 Log in to your GoDaddy Account. Click on "My Account" at the top left. Click on "Domains". Click on the "Launch" button for the domain you want to create the nameservers for. Find........
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    This is a handy link and list of all the relevant Directadmin log files and related servers. http://help.directadmin.com/item.php?id=11 DirectAdmin: /var/log/directadmin/error.log /var/log/directadmin/errortaskq.log /var/log/directadmin/system.log /var/log/directadmin/security.log Apache:........
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    This is very handy if you're too busy and don't have time to download whatever files you need. The -D specifies the domains allowed, this is because I specified -H which means foreign hosts are allowed, if you don't restrict them you'll end up going to the whole internet via ads and other links just like a search Engine would follow. -l 0 specifies to go deep, to as many levels as possible/as exist. -e robots=off is important because robots.txt often says you can't vie........
  • 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. &........
  • Yahoo Mail (email) DNS Server Out Of Date Problems


    I don't expect this to be solved soon but some of Yahoo's DNS servers are out of whack. I changed the IPs of some nameservers of some domains and now most Yahoo users can't e-mail to those domains! As you can see below by the "No MX or A records for mychangedomain.com", now Yahoo's DNS/mailserver DNS cache is wrong. You would think they would at least have cached the old incorrect records, but instead for some reason their DNS cache has no entry and doesn't seem........
  • Plesk Get List of E-mail Users & Aliases


    When migrating away from Plesk I couldn't figure out an easy way to get a straight list of all e-mails, but here is where I found the solution: http://nakuls77.wordpress.com/2008/08/30/details-of-email-ftp-database-users-from-psa-database/ mysql> SELECT mail.mail_name, accounts.password, domains.name FROM mail, accounts, domains WHERE domains.id=mail.dom_id AND mail.account_id=accounts.id; mysql> SELECT CONCAT(mail.mail_name,’@’,domains.name) AS Em........
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    genuine.com/IN: loading master file genuine.com.zone: file not found _default/genuine.com/IN: file not found I always found it silly that no one really talks about this and apparently many like me and even control panels like Plesk were still using hard paths. I always thought "why can't I just specify the name of the zone file and have bind find it". Surely the default search path must be /var/named or somewhere else but there is no such thing.........
  • Plesk: Backup Domains from the CLI - it's quicker


    Plesk 8.6 CLI backup: /usr/local/psa/bin/pleskbackup domains domain.com This is a much better way of doing it and of course it can be scripted, it's a real pain to point, click and wait for Plesk to backup domains (and yes Iknow you could do all of them in a single client file but this is not desirable for my situation).........
  • Importing Plesk 8.6 Backup to Virtualmin: Validating migration file .. .. validation failed : XML::Simple Perl module is not installed


    Importing Plesk 8.6 Backup to Virtualmin: Validating migration file .. .. validation failed : XML::Simple Perl module is not installed Solution is to install the correct module: perl -MCPAN -e 'install XML::Simple' Migrating a single domain works just fine, but it doesn't work with a full client backup containing multiple domains.........
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