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Command to check DDOS on Server

By Prasad Naik
September 7, 2026

Recently we had an issue on server where server load was minimal However none of website were opening While investigating we found the issue was due to DDOS on server Commmand netstat -plan| grep -E ‘:443|:80’ |awk {‘print $5’}|cut -d: -f 1|sort|uniq -c|sort -n | tail -15 Showed up excessecive causing IP address We blocked […]

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Change user in Ubuntu OS

By Prasad Naik
June 25, 2026

Normally Ubuntu allows you to install OS as non root username So you need to login to server as non root user and run command mentioned below to login as root user sudo -i Once you login as root user change below mentioned parameter in /etc/ssh/sshd_config and uncomment PermitRootLogin paramter and change to to yes […]

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ERROR “Let’s Encrypt™” DNS DCV error on autoSSL cpanel

By Prasad Naik
June 24, 2026

ERROR “Let’s Encrypt™” DNS DCV error (*.xtklaos.com): 400 urn:ietf:params:acme:error:dns (There was a problem with a DNS query) (DNS problem: looking up TXT for _acme-challenge.xxxtklaos.com: DNSSEC: DNSKEY Missing: validation failure <_acme-challenge.xxxtklaos.com. TXT IN>: No DNSKEY record [misc failure] from 142.214.184.xxx for key xxxtklaos.com. while building chain of trust) Was getting an issue where autoSSL was giving […]

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A DNS entry for “rexxxxxxl.com” already exists

By Prasad Naik
January 29, 2025

The User had removed his addon domain from cPanel. However while adding back there was wrror coming up “A DNS entry for “rexxxxxxl.com” already exists” T The issue is likely due to leftover DNS configurations from removed domains. Running the /scripts/cleandns script should correct the issue. Running command /scripts/cleandns fixed the issue 🙂

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WordPress Error : Missing a temporary folder

By Prasad Naik
October 7, 2024

You may get an error while uploading images in wordpress with error The error message said – Missing a temporary folder The solution to this issue is Open wp-config.php in server Search for WP_TEMP_DIR in wp-config and check the path Usually its wp-content/Temp Check if this folders exists using ls -al /home/username /public_html/wp-content/Temp If folder […]

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“Let’s Encrypt to revoke 3 million certificates on March 4 due to software bug”

By Prasad Naik
March 4, 2020

If you want to double check whether a given hostname still needs its certificate replaced, you can use the tool at https://checkhost.unboundtest.com/ Example : The certificate currently available on hostname is OK. It is not one of the certificates affected by the Let’s Encrypt CAA rechecking problem. Its serial number is 04534d6558f552c3c7e8ab4768d4f6f32xx6

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Magento error Invalid command ‘

By Prasad Naik
December 23, 2018

Invalid command ‘<IfVersion’, perhaps misspelled or defined by a module not included in the server configuration The above error is due to missing mod_version which needs to be added in apache using easyapache it was fixed once the mod_version module was added          

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[ERROR] Can’t init tc log Mariadb

By Prasad Naik
March 30, 2018

2018-03-30 2:06:19 139671858284288 [Note] InnoDB: Dumping buffer pool(s) not yet started 2018-03-30 2:06:19 139672598403328 [Note] Plugin ‘FEEDBACK’ is disabled. 2018-03-30 2:06:19 139672598403328 [Note] Recovering after a crash using tc.log 2018-03-30 2:06:19 139672598403328 [ERROR] Can’t init tc log 2018-03-30 2:06:19 139672598403328 [ERROR] Aborting Was getting above error in mysql errorlog The solution to this issue was […]

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umount: /backup: device is busy

By Prasad Naik
March 12, 2018

While trying to unmount a secondary drive I see below error umount: /backup: device is busy. (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1)) The issue was due to the drive /dev/sdb being used by some process Below is the process on how to find process […]

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The system could not create the user “triltch” because it conflicts with an unmanaged MySQL database user and an unmanaged PostgreSQL database user

By Prasad Naik
February 21, 2018

While creating a new account in server was getting below error The issue was due to mysql user already being present in server root@srv1 [~]# /scripts/wwwacct trill.com tritch hood773ud +===================================+ | New Account Info | +===================================+ | Domain: trill.com | UserName: tritch | PassWord: hood773ud +===================================+ This ok? yes Checking input data……Done Validating system setup……Done […]

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SMTP AUTH is required for message submission on port 587

By Prasad Naik
January 17, 2018

The ‘SMTP AUTH’ error usually happens when users try to send mails without properly authenticating their mail account in email clients such as Outlook or Thunderbird. What causes the error ‘SMTP AUTH is required for message submission on port 587’ in cPanel/WHM servers With the latest cPanel/WHM update, email accounts that were working fine till […]

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Your system has run out of available ip addresses, or you do not have permission to use any more ip addresses WHMCS

By Prasad Naik
December 20, 2017

While activating a new account I could see an error “Your system has run out of available ip addresses, or you do not have permission to use any more ip addresses” The issue was due to the server running out of spare dedicated IP address The issue can be resolved in 2 ways 1) Adding […]

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