The sip:provider CE system upgrade to mr4.5.1 will be performed in a couple of tasks:

	ensure you are using Sipwise APT repositories. Public Debian mirrors may not provide packages for old Debian releases anymore. Also they can be outdated. Consider to use Sipwise repositories for the time of upgrade.

Execute the following commands as root:

echo "# Please visit /etc/apt/sources.list.d/ instead." > /etc/apt/sources.list

mkdir -p /etc/apt/sources.list.d
for file in /etc/apt/sources.list.d/*.list ; do mv "${file}" "${file}.DISABLED" ; done

NGCP_CURRENT_VERSION=$(cat /etc/ngcp_version)
cat > /etc/apt/sources.list.d/debian.list << EOF
# Debian repositories, deployed via upgrade ${NGCP_CURRENT_VERSION}->mr4.5.1
deb https://debian.sipwise.com/debian/ jessie main contrib non-free
#deb-src https://debian.sipwise.com/debian/ jessie main contrib non-free
#
deb https://debian.sipwise.com/debian-security/ jessie-security main contrib non-free
#deb-src https://debian.sipwise.com/debian-security/ jessie-security main contrib non-free
#
deb https://debian.sipwise.com/debian/ jessie-updates main contrib non-free
#deb-src https://debian.sipwise.com/debian/ jessie-updates main contrib non-free
EOF

NGCP_CURRENT_VERSION=$(cat /etc/ngcp_version)
cat > /etc/apt/sources.list.d/sipwise.list << EOF
# NGCP_MANAGED_FILE
# Sipwise repository, deployed via upgrade ${NGCP_CURRENT_VERSION}->mr4.5.1
deb https://deb.sipwise.com/spce/${NGCP_CURRENT_VERSION}/ jessie main
#deb-src https://deb.sipwise.com/spce/${NGCP_CURRENT_VERSION}/ jessie main
EOF

Run "apt-get update" and ensure you have no warnings/errors here.

For upgrading the sip:provider CE to release mr4.5.1, execute the following commands:

NGCP_CURRENT_VERSION=$(cat /etc/ngcp_version)
sed -i "s/$NGCP_CURRENT_VERSION/mr4.5.1/" /etc/apt/sources.list.d/sipwise.list
apt-get update
apt-get install ngcp-upgrade-ce

Run the upgrade script as root like this:

ngcp-upgrade

	sip:provider CE can be upgraded to mr4.5.1 from previous release or previous build only. The script ngcp-upgrade will find all the possible destination releases for the upgrade and allow to choose the proper one.

The upgrade script will ask you to confirm that you want to start. Read the given information carefully, and if you agree, proceed with y.

The upgrade process will take several minutes, depending on your network connection and server performance. After everything has been updated successfully, it will finally ask you to reboot your system. Confirm to let the system reboot (it will boot with an updated kernel).

Once up again, double-check your config file /etc/ngcp-config/config.yml (sections will be rearranged now and will contain more parameters) and your domain/subscriber/peer configuration and test the setup. You can find a backup of some important configuration files of your existing installation under /var/backup/ngcp-mr4.5.1-* (where * is a place holder for a timestamp) in case you need to roll back something at any time. A log file of the upgrade procedure is available at /var/backup/ngcp-mr4.5.1-\*/upgrade.log.

	sip:provider CE mr4.5.1 requires at least 2GB of RAM available as the minimum requirements of the installation section, otherwise certain features will not work and you will run into arbitrary issues.