Report Mail delivery - This message was rejected at smtp time by an rbl

[renato.figueiredo]

I'm getting several logs in my e-mail delivery report but I don't know how to proceed, since if our server has an open relay, I don't know. Does anyone have any idea how this issue can be resolved?

[System]	May 30, 2022, 4:31:16 PM	0	[email protected]	1nvl6m-000CgC-vG	host lookup did not complete
	[System]	May 30, 2022, 4:31:16 PM	0	[email protected]	1nvl6h-000ClW-vG	host lookup did not complete
	[System]	May 30, 2022, 4:31:16 PM	0	[email protected]	1nvl6h-000Cm6-vG	host lookup did not complete
	[System]	May 30, 2022, 4:31:16 PM	0	[email protected]	1nvl6g-000ClS-vG	host lookup did not complete
	[System]	May 30, 2022, 4:31:16 PM	0	[email protected]	1nvl6f-000Cma-vG	host lookup did not complete
	[System]	May 30, 2022, 4:31:16 PM	0	[email protected]	1nvl6d-000Cl0-vG	host lookup did not complete
	[System]	May 30, 2022, 4:31:16 PM	0	[email protected]	1nvl6c-000CmK-vG	host lookup did not complete

 

[kodeslogic]

I would first check server has good resolvers using the below command:

/scripts/check_unreliable_resolvers

 

[Rachel S]

The error "host lookup did not complete" occurs when the server can't resolve the receivers' domain. It's usually because of the nameservers defined in /etc/resolv.conf or WHM >> Resolver Configuration. This can also happen if your domain's MX record does not resolve to an IP address.

Here's how you can test the server open relay:
Using the MAIL FROM and RCPT TO commands, you can telnet to the server and send an email to another domain. Your server is an open relay if the final response code is 250 and no authentication is asked.

Try the following steps if your email has been denied because of an RBL:

The IP address can be in error.

Once you find the IP address, you need to scan any machines/devices related to that particular IP address and kindly remove the malware/spyware/viruses.

Open Abusix Intelligence | Abusix to check which RBLs the IP address is on and request de-listing from the relevant section.

Once you have done de-listing the IP address, you will be able to send the email again.