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Cannot resolve IPv6 hosts

Discussion in 'General Discussion' started by vexx, Jan 31, 2018.

  1. vexx

    vexx Registered

    May 1, 2012
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    Hey there,

    What started this problem was me trying to send email using and getting a major lag until it finally connected (after 2-3 mins). Using telnet to connect to the smtp I learned that it tries to resolve the IPv6 ip of, give a timeout after a while and then retry with IPv4 which works instantly. Using the openssl command on the same smtp has the same effect.

    I have attached a screenshot of my telnet log. I'm not sure how to approach this, initially, I thought exim had a problem and i disabled ipv6 there, but no effect. The resolve.conf uses google's NS correct, so I'm not sure what am I missing. Do i need to prioriteze IPv4 over IPV6? How do I do this?


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  2. cPanelMichael

    cPanelMichael Forums Analyst
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    Apr 11, 2011
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