Before installing cpan packages check that there are no PERL environment variables set. If there are, packages may be installed into root's home directory and processes may not work when started on system boot. You should remove the variables from /root/.bashrc (or wherever set them) and then logout and login to the shell to clear the variables. To check for PERL environment variables run:

• env | grep PERL

To upgrade from OpenSIPS or OpenSER to Kamailio on a single machine

1. Do:
   • cpanm Math::BigInt::FastCalc
   • enswitch install kamailio
   • vi /etc/kamailio/kamailio.cfg # and set the database URL
   • service openser stop
   • service opensips stop
   • enswitch kamailio_tables
   • service kamailio restart
2. If running Debian or Ubuntu, do:
   • rm -f /etc/init.d/opensips /etc/init.d/openser
   • update-rc.d openser remove
   • update-rc.d opensips remove
3. If running CentOS, Fedora, or Redhat, do:
   • chkconfig openser off
   • chkconfig opensips off
   • rm -f /etc/init.d/opensips /etc/init.d/openser

To upgrade from OpenSIPS or OpenSER to Kamailio on a pair of machines running corosync and pacemaker

Do each command on both machines before continuing to the next command.

1. Do, on both machines simultaneously:
   • cpanm Math::BigInt::FastCalc
   • enswitch install kamailio-cp
   • vi /etc/kamailio/kamailio.cfg # and set the database URL
   • crm resource stop opensips # change "opensips" to "openser" if using openser
   • crm resource delete opensips # change "opensips" to "openser" if using openser
   • crm configure primitive kamailio systemd:kamailio op monitor interval="30s"
   • crm configure group enswitch ip kamailio enswitch_messaged enswitch_sipd enswitch_blfd
   • enswitch kamailio_tables # only needs done on one machine
   • crm resource start kamailio
2. Test a failover and fail back.

Should you need to revert to OpenSIPS, the table_version for location is 1004.