How to catch broadcast flood on D-Link switches

I noticed once in one common network jumps in broadcast traffic, I was able to detect naturally quickly, since I had previously set up monitoring via graphs and triggers using Zabbix. I looked at the graphs of broadcast traffic from the ports of the main switch, from here it was clear where he started to go, and so we determined the chain to the client switch and port. In the Zabbix monitoring system, it is convenient to configure triggers that trigger when the limit of broadcast traffic is exceeded and report this on the screen, email to the administrator, etc.

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cPanel. Solving the Failed to find user “” from expanded string

Once on the same server as cPanel, after changing the settings in the WHM menu “Server Configuration” – “Settings”, email stopped working, I found the following error in the logs:

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How to solve Cpanel::MailAuth: cphulk blocked login for user to access service ‘mail’

I noticed somehow that mail from Cpanel does not open through the Web Roundcube, SquirrelMail, Horde, and also you can’t connect to mail from PHP scripts.

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