I'm having problems with my internet connection. Firefox was really slow. I fix the problem setting network.dns.disableIPv6;true in about:config.
But I still having problems with other software, like curl. Any curl request takes 20 seconds to return in Ubuntu. With Windows they return instantly. I also have some Java code that does some http requests, which also takes 20 seconds and in Windows returns instantly.
I already tried
but with no results.
echo 'blacklist ipv6' | sudo tee -a '/etc/modprobe.d/blacklist.local' >/dev/null
echo "#disable ipv6" | sudo tee -a /etc/sysctl.conf
echo "net.ipv6.conf.all.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf
echo "net.ipv6.conf.default.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf
echo "net.ipv6.conf.lo.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf
Does anyone have some clue on what could be wrong?