When a Data collector is on a Linux server and is restarted, CDR collection may stop working.
The Linux Firewall rules were not saved. During reboot, the firewall reverts to the last saved settings.
To fix this issue, run the following command on the Vyopta Collector Linux Server. The "save" option at the end will make the change permanent.
sudo iptables -t nat -A PREROUTING -p tcp -m tcp --dport 21 -j REDIRECT --to-ports 2121
sudo service iptables save
For more information on installing the Vyopta Collector on Linux, please refer to the Vyopta Knowledge Base article.