Upgrade to version 2.4 from version 1.6

First perform all the steps explained in upgrading from version 1.6 to 2.0, then the steps Upgrade to version 2.1 from version 2.0, then all the steps described in Upgrade to version 2.2 from version 2.1 and then perform all the steps described in Upgrading to version 2.3 from version 2.2, and then all the steps explained in Upgrading to version 2.4 from version 2.3.

Upgrade to version 2.4 from version 1.5

First perform all steps for upgrading from version 1.5 to 1.6, and then perform all steps for upgrading from version 1.6 to 2.0, and then perform all the steps for upgrading from version 2.0 to version 2.1, and then perform all steps for upgrading from version 2.1 to 2.2 and then all the steps explained in Upgrading to version 2.3 from version 2.2, and then all the steps explained in Upgrading to version 2.4 from version 2.3.

Upgrade to version 2.4 from version 1.4

First perform all steps for upgrading from version 1.4 to 1.5, and then perform the steps of upgrading from version 1.5 to 1.6, and then perform all steps for upgrading from version 1.6 to 2.0 and then perform all the steps for upgrading from version 2.0 to version 2.1, and then perform all steps for upgrading from version 2.1 to 2.2 and then all the steps explained in Upgrading to version 2.3 from version 2.2, and then all the steps explained in Upgrading to version 2.4 from version 2.3.