prevent IPV4 to IPV6 translation

[diginfo]

Hi;

O/S: Ubuntu 16.

Been using the same SNIPROXY server for a new years and just setup a new one, but are having some problems that I think may be related to address translation V4 > V6

2018-03-31 10:56:48 25.119.154.XXX:53181 -> XXX.166.170.XXX:443 -> [2a02:26f0:d3:189::f33]:443 [connected-tv.files.bbci.co.uk] 7/7 bytes tx 517/1034 bytes rx 0.003 seconds

As you can see from this log, the IPV4 address appears to be translated to an IPV6 address "[2a02:26f0:d3:189::f33]" if I understand the log correctly ?

In the browser I am getting a lot of errors like

net::ERR_SSL_VERSION_OR_CIPHER_MISMATCH
net::ERR_ABORTED
net::ERR_SSL_VERSION_INTERFERENCE

and I think it mat be related as the sites I am having problems with all appear to have this V4 > V6 translation in the logs, the sites that don't have that are OK ??

Is it possible to prevent this translation either in sniproxy or elsewhere ?

I have added this to /etc/sysctl.conf but it does not appear to help:

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1

Any suggestions ?

[dlundquist]

You want to use the resolver ipv4_only config option.