Trunk not authenticates after falling internet link

Hello, works with asterisk (11.7.0) have a recurring problem, when there is some drop in internet links lines (trunk) lose authentication with the operator, however even running the command “sip reload” not back gets status "UNREACHABLE "can help me with this? please.

This seems to be related to this old bug “
If Asterisk loses internet connectivity or DNS, it stops responding to all SIP devices and trunks, and all extensions lose connectivity”

Good morning Friend, I read the contents put some steps to follow to disable DNS Lookup not worked. The failure occurs when my internet link failure, however when not back the trunk authenticates again, I have to restart the entire server, as it keeps a cache and for this reason only after a reboot to return.