Rails Mailer “Net::OpenTimeout: execution expired” Exception on production server only

Question

I am using Ruby MRI 2.0.0 and Rails 3.2.12 on a Ubuntu 12.04 TLS VPS and attempting to setup email notifications in my app. It was working fine a few days ago, but n

Answer 1

I added these to /etc/gai.conf in CentOS7 and it worked.

label       ::1/128        0
label       ::/0           1
label       2002::/16      2
label       ::/96          3
label       ::ffff:0:0/96  4
precedence  ::1/128        50
precedence  ::/0           40
precedence  2002::/16      30
precedence  ::/96          20
precedence  ::ffff:0:0/96  100

http://blog.asiantuntijakaveri.fi/2014/12/prefer-ipv4-over-ipv6-on-centos-6.html:title