DNS records check

Question

Hi All

i dont have much knowledge on email gateway. I am not sure is this correct forum to post this.
One external user has sent an email and the email is rejected at email gateway with the information Anti-Spoofing Lockout.

I can see the below information at the gateway.
Remote Server Info:lb-192-168-123-9.contoso.com(i changed ip here)
IP Address: 192.168.193.5

When i check for spf record in mxtoolbox i found the below info
v=spf1 mx a:spf.contoso.com -all

what do i need to validate to allow the sender to safe senders list.

1. How can i check if sending servers are on spf records.
2. Any other validation do i need to check like dmarc or dkim

Answer 1

You can check all that here:
https://mxtoolbox.com/DMARC.aspx

https://mxtoolbox.com/spf.aspx

https://mxtoolbox.com/t/test/networktoolsdevt?command=dkim