diff --git a/etc/kayobe/bifrost.yml b/etc/kayobe/bifrost.yml
index 0bfcec7..9cabe81 100644
--- a/etc/kayobe/bifrost.yml
+++ b/etc/kayobe/bifrost.yml
@@ -86,6 +86,9 @@
 #kolla_bifrost_inspector_port_addition:
 
 # List of extra kernel parameters for the inspector default PXE configuration.
+# Default is {{ inspector_extra_kernel_options }}, defined in inspector.yml.
+# When customising this variable, the default extra kernel parameters should be
+# kept to retain full node inspection capabilities.
 #kolla_bifrost_inspector_extra_kernel_options:
 
 # List of introspection rules for Bifrost's Ironic Inspector service.
diff --git a/etc/kayobe/infra-vms.yml b/etc/kayobe/infra-vms.yml
index c8aec1c..dc7ff23 100644
--- a/etc/kayobe/infra-vms.yml
+++ b/etc/kayobe/infra-vms.yml
@@ -32,7 +32,7 @@
 # Base image for the infra VM root volume. Default is
 # "https://cloud-images.ubuntu.com/focal/current/focal-server-cloudimg-amd64.img"
 # when os_distribution is "ubuntu", or
-# "https://cloud.centos.org/centos/8-stream/x86_64/images/CentOS-Stream-GenericCloud-8-20210210.0.x86_64.qcow2"
+# "https://cloud.centos.org/centos/8-stream/x86_64/images/CentOS-Stream-GenericCloud-8-20210603.0.x86_64.qcow2"
 # otherwise.
 #infra_vm_root_image:
 
diff --git a/etc/kayobe/ipa.yml b/etc/kayobe/ipa.yml
index e0f2094..519ca2a 100644
--- a/etc/kayobe/ipa.yml
+++ b/etc/kayobe/ipa.yml
@@ -16,7 +16,7 @@
 # URL of IPA builder source repository.
 #ipa_builder_source_url:
 
-# Version of IPA builder source repository. Default is master.
+# Version of IPA builder source repository. Default is {{ openstack_branch }}.
 #ipa_builder_source_version:
 
 # List of default Diskimage Builder (DIB) elements to use when building IPA
diff --git a/etc/kayobe/kolla.yml b/etc/kayobe/kolla.yml
index a07406f..9e37380 100644
--- a/etc/kayobe/kolla.yml
+++ b/etc/kayobe/kolla.yml
@@ -479,6 +479,21 @@
 # default.
 #kolla_internal_fqdn_cacert:
 
+###############################################################################
+# Proxy configuration
+
+# HTTP proxy URL (format: http(s)://[user:password@]proxy_name:port) used by
+# Kolla. Default value is "{{ http_proxy }}".
+#kolla_http_proxy:
+
+# HTTPS proxy URL (format: http(s)://[user:password@]proxy_name:port) used by
+# Kolla. Default value is "{{ https_proxy }}".
+#kolla_https_proxy:
+
+# List of domains, hostnames, IP addresses and networks for which no proxy is
+# used. Default value is "{{ no_proxy }}".
+#kolla_no_proxy:
+
 ###############################################################################
 # Dummy variable to allow Ansible to accept this file.
 workaround_ansible_issue_8743: yes
diff --git a/etc/kayobe/networks.yml b/etc/kayobe/networks.yml
index eabe52e..9043116 100644
--- a/etc/kayobe/networks.yml
+++ b/etc/kayobe/networks.yml
@@ -196,6 +196,15 @@
 # 'name' items. These tables will be added to /etc/iproute2/rt_tables.
 #network_route_tables:
 
+###############################################################################
+# Network connectivity check configuration.
+
+# External IP address to check. Default is 8.8.8.8.
+#nc_external_ip:
+
+# External hostname to check. Default is google.com.
+#nc_external_hostname:
+
 ###############################################################################
 # Dummy variable to allow Ansible to accept this file.
 workaround_ansible_issue_8743: yes
diff --git a/etc/kayobe/openstack.yml b/etc/kayobe/openstack.yml
index f2fe55a..1acfd07 100644
--- a/etc/kayobe/openstack.yml
+++ b/etc/kayobe/openstack.yml
@@ -2,10 +2,10 @@
 ###############################################################################
 # OpenStack release configuration.
 
-# Name of the current OpenStack release. Default is "xena".
+# Name of the current OpenStack release. Default is "master".
 #openstack_release:
 
-# Name of the current OpenStack branch. Default is "stable/xena".
+# Name of the current OpenStack branch. Default is "master".
 #openstack_branch:
 
 ###############################################################################
diff --git a/etc/kayobe/overcloud-dib.yml b/etc/kayobe/overcloud-dib.yml
new file mode 100644
index 0000000..0a95c97
--- /dev/null
+++ b/etc/kayobe/overcloud-dib.yml
@@ -0,0 +1,55 @@
+---
+# Overcloud host disk image configuration.
+
+###############################################################################
+# Diskimage-builder configuration for overcloud host disk images.
+
+# Whether to build host disk images with DIB directly instead of through
+# Bifrost. Setting it to true disables Bifrost image build and allows images to
+# be built with the `kayobe overcloud host image build` command. Default value
+# is False. This will change in a future release.
+#overcloud_dib_build_host_images:
+
+# DIB base OS element. Default is {{ os_distribution }}.
+#overcloud_dib_os_element:
+
+# DIB image OS release. Default is {{ os_release }}.
+#overcloud_dib_os_release:
+
+# List of default DIB elements. Default is ["centos", "cloud-init-datasources",
+# "disable-selinux", "enable-serial-console", "vm"] when
+# overcloud_dib_os_element is "centos", or ["ubuntu", "cloud-init-datasources",
+# "enable-serial-console", "vm"] when overcloud_dib_os_element is "ubuntu".
+#overcloud_dib_elements_default:
+
+# List of additional DIB elements. Default is none.
+#overcloud_dib_elements_extra:
+
+# List of DIB elements. Default is a combination of
+# overcloud_dib_elements_default and overcloud_dib_elements_extra.
+#overcloud_dib_elements:
+
+# DIB default environment variables. Default is
+# {"DIB_BOOTLOADER_DEFAULT_CMDLINE": "nofb nomodeset gfxpayload=text
+# net.ifnames=1", "DIB_CLOUD_INIT_DATASOURCES": "ConfigDrive", "DIB_RELEASE":
+# "{{ overcloud_dib_os_release }}"}.
+#overcloud_dib_env_vars_default:
+
+# DIB additional environment variables. Default is none.
+#overcloud_dib_env_vars_extra:
+
+# DIB environment variables. Default is combination of
+# overcloud_dib_env_vars_default and overcloud_dib_env_vars_extra.
+#overcloud_dib_env_vars:
+
+# List of DIB packages to install. Default is to install no extra packages.
+#overcloud_dib_packages:
+
+# Upper constraints file for installing packages in the virtual environment
+# used for building overcloud host disk images. Default is {{
+# pip_upper_constraints_file }}.
+#overcloud_dib_upper_constraints_file:
+
+###############################################################################
+# Dummy variable to allow Ansible to accept this file.
+workaround_ansible_issue_8743: yes
diff --git a/etc/kayobe/proxy.yml b/etc/kayobe/proxy.yml
new file mode 100644
index 0000000..aaf9389
--- /dev/null
+++ b/etc/kayobe/proxy.yml
@@ -0,0 +1,16 @@
+---
+###############################################################################
+# Configuration of HTTP(S) proxies.
+
+# HTTP proxy URL (format: http(s)://[user:password@]proxy_name:port). By
+# default no proxy is used.
+#http_proxy:
+
+# HTTPS proxy URL (format: http(s)://[user:password@]proxy_name:port). By
+# default no proxy is used.
+#https_proxy:
+
+# List of domains, hostnames, IP addresses and networks for which no proxy is
+# used. Defaults to ["127.0.0.1", "localhost", "{{ docker_registry }}"]. This
+# is configured only if either http_proxy or https_proxy is set.
+#no_proxy:
diff --git a/etc/kayobe/seed-hypervisor.yml b/etc/kayobe/seed-hypervisor.yml
index 26cfbe5..ac72fcd 100644
--- a/etc/kayobe/seed-hypervisor.yml
+++ b/etc/kayobe/seed-hypervisor.yml
@@ -18,6 +18,9 @@
 # List of extra networks to which seed hypervisor nodes are attached.
 #seed_hypervisor_extra_network_interfaces:
 
+# Whether to enable SNAT on seed hypervisor node. Default is false.
+#seed_hypervisor_enable_snat:
+
 ###############################################################################
 # Seed hypervisor node software RAID configuration.
 
diff --git a/etc/kayobe/seed-vm.yml b/etc/kayobe/seed-vm.yml
index 9ad7a74..8e20fc7 100644
--- a/etc/kayobe/seed-vm.yml
+++ b/etc/kayobe/seed-vm.yml
@@ -26,7 +26,7 @@
 # Base image for the seed VM root volume. Default is
 # "https://cloud-images.ubuntu.com/focal/current/focal-server-cloudimg-amd64.img"
 # when os_distribution is "ubuntu", or
-# "https://cloud.centos.org/centos/8-stream/x86_64/images/CentOS-Stream-GenericCloud-8-20210210.0.x86_64.qcow2"
+# "https://cloud.centos.org/centos/8-stream/x86_64/images/CentOS-Stream-GenericCloud-8-20210603.0.x86_64.qcow2"
 # otherwise.
 #seed_vm_root_image: