Rename setup-mtu-t1 argument because it is misleading

setup-mtu-t1 argument name is misleading as it suggest that
it will do something with the MTU value, but it really just reduces
DHCP agent t1 timer. The fact that this commnad will have a side
effect of getting a new MTU value from DHCP should not be part
of the argument name. This is based on customer's feedback.
I am keeping backward compatibility for setup-mtu-t1 argument
in order not to break any existing tools that might depend on it.

Change-Id: I939b21fa998c80cf921efeae3e8fa8c2b4ef4f50
(cherry picked from commit c2fb0b1)

Author: mtomaska

doc/source/ovn/migration.rst

@@ -21,9 +21,9 @@ adjustments, prepare the environment for the procedure.
 
 Subsequent steps start the migration via Ansible.
 
-Plan for a 24-hour wait after the setup-mtu-t1 step to allow VMs to catch up
-with the new MTU size. The default neutron ML2/OVS configuration has a
-dhcp_lease_duration of 86400 seconds (24h).
+Plan for a 24-hour wait after the reduce-dhcp-t1 step to allow VMs to catch up
+with the new MTU size from the DHCP server. The default neutron ML2/OVS
+configuration has a dhcp_lease_duration of 86400 seconds (24h).
 
 Also, if there are instances using static IP assignment, the administrator
 should be ready to update the MTU of those instances to the new value of 8
@@ -182,11 +182,11 @@ Perform the following steps in the undercloud
    with the migration playbooks.
 
 
-6. Run ``ovn_migration.sh setup-mtu-t1``
+6. Run ``ovn_migration.sh reduce-dhcp-t1``
 
    .. code-block:: console
 
-      $ ovn_migration.sh setup-mtu-t1
+      $ ovn_migration.sh reduce-dhcp-t1
 
 
    This lowers the T1 parameter

tools/ovn_migration/infrared/tripleo-ovn-migration/main.yml

@@ -166,10 +166,10 @@
                   set -o pipefail &&
                   {{ ovn_migration_working_dir }}/start-ovn-migration.sh generate-inventory 2>&1 > {{ ovn_migration_working_dir}}/generate-inventory.log
 
-            - name: Set MTU T1
+            - name: Set DHCP T1 timer
               shell:
                   set -o pipefail &&
-                  {{ ovn_migration_working_dir }}/start-ovn-migration.sh setup-mtu-t1 2>&1 > {{ ovn_migration_working_dir}}/setup-mtu-t1.log
+                  {{ ovn_migration_working_dir }}/start-ovn-migration.sh reduce-dhcp-t1 2>&1 > {{ ovn_migration_working_dir}}/reduce-dhcp-t1.log
 
             - name: Reduce mtu of the pre migration networks
               shell:

tools/ovn_migration/tripleo_environment/ovn_migration.sh

@@ -238,7 +238,7 @@ EOF
     cat hosts_for_migration
     echo "***************************************"
     echo "Generated the inventory file - hosts_for_migration"
-    echo "Please review the file before running the next command - setup-mtu-t1"
+    echo "Please review the file before running the next command - reduce-dhcp-t1"
 }
 
 # Check if source inventory exists
@@ -283,7 +283,7 @@ oc_check_network_mtu() {
     return $?
 }
 
-setup_mtu_t1() {
+reduce_dhcp_t1() {
     # Run the ansible playbook to reduce the DHCP T1 parameter in
     # dhcp_agent.ini in all the overcloud nodes where dhcp agent is running.
     ansible-playbook  -vv $OPT_WORKDIR/playbooks/reduce-dhcp-renewal-time.yml \
@@ -349,7 +349,7 @@ complete details. This script needs to be run in 5 steps.
 
            Generates the inventory file
 
- Step 2 -> ovn_migration.sh setup-mtu-t1
+ Step 2 -> ovn_migration.sh reduce-dhcp-t1 (deprecated name setup-mtu-t1)
 
            Sets the DHCP renewal T1 to 30 seconds. After this step you will
            need to wait at least 24h for the change to be propagated to all
@@ -386,9 +386,13 @@ case $command in
         ret_val=$?
         ;;
 
-    setup-mtu-t1)
+    reduce-dhcp-t1 | setup-mtu-t1)
+        if [[ $command = 'setup-mtu-t1' ]]; then
+            echo -e "Warning: setup-mtu-t1 argument was renamed."\
+                    "Use reduce-dhcp-t1 argument instead."
+        fi
         check_for_necessary_files
-        setup_mtu_t1
+        reduce_dhcp_t1
         ret_val=$?;;
 
     reduce-mtu)