Internet on the distro, but asterisk not connecting to trunks


I’m running FreePBX Distro 6.12.65-28 as a virtual machine (kvm & libvirt). The host connects to the internet via DSL. After a reboot (e. g. powercut) some time for the DSL sync is needed and therefore for the internet connection to be established. So no internet while the VM boots up (SSD, so its pretty fast). When the link is established the host and the vm have internet connection (ping, wget, yum update etc. working on the FPBX VM) but asterisk doesn’t connect to the trunk (no connection). Even not after waiting for ~10 minutes. If I restart the vm with an established internet connection on the host asterisk connects to the trunk without a problem. maybe just restarting asterisk would also help, but I coudn’t try yet (production environment).

a workaround could be, in case the asterisk restart would work, to put “sleep 60s; amportal restart” in rc.local.

any ideas how to fix this properly?