diff --git a/roles/system_check/tasks/_placement.yml b/roles/system_check/tasks/_placement.yml
new file mode 100644
index 0000000..aaf43b7
--- /dev/null
+++ b/roles/system_check/tasks/_placement.yml
@@ -0,0 +1,243 @@
+---
+- name: Collect the boot media this run attaches
+  ansible.builtin.set_fact:
+    system_check_media: >-
+      {{ [{'name': 'boot_iso', 'value': boot_iso}]
+         + ([{'name': 'rhel_iso', 'value': rhel_iso}]
+            if (rhel_iso | default('') | string | length > 0) else []) }}
+
+- name: Verify vCenter boot media and placement target
+  when: hypervisor_type == "vmware"
+  delegate_to: localhost
+  become: false
+  module_defaults:
+    group/community.vmware.vmware:
+      hostname: "{{ hypervisor_cfg.url }}"
+      username: "{{ hypervisor_cfg.username }}"
+      password: "{{ hypervisor_cfg.password }}"
+      validate_certs: "{{ hypervisor_cfg.certs | bool }}"
+  block:
+    - name: Assert the boot media is a datastore path
+      ansible.builtin.assert:
+        that:
+          - item.value is match('^\\[[^\\]]+\\]\\s*\\S')
+        fail_msg: |
+          {{ item.name }} is "{{ item.value }}", which is not a vSphere datastore path.
+          Set {{ item.name }} to the form "[datastore] folder/file.iso",
+          for example "[ssdmsa_lun1] ISO/SGBoot-2026.06.09-x86_64.iso".
+        quiet: true
+      loop: "{{ system_check_media }}"
+      loop_control:
+        label: "{{ item.name }}"
+
+    - name: Resolve the datastores this run depends on
+      ansible.builtin.set_fact:
+        system_check_datastores_needed: >-
+          {%- set ns = namespace(refs=[{'source': 'hypervisor.storage',
+                                        'datastore': hypervisor_cfg.storage, 'path': ''}]) -%}
+          {%- for media in system_check_media -%}
+          {%- set ns.refs = ns.refs + [{
+                'source': media.name,
+                'datastore': media.value | regex_replace('^\\[([^\\]]+)\\].*$', '\\1'),
+                'path': media.value | regex_replace('^\\[[^\\]]+\\]\\s*', '')
+              }] -%}
+          {%- endfor -%}
+          {{ ns.refs }}
+
+    - name: Query the ESXi placement host
+      when: hypervisor_cfg.node | default('') | length > 0
+      community.vmware.vmware_host_facts:
+        esxi_hostname: "{{ hypervisor_cfg.node }}"
+      register: system_check_esxi
+      delegate_facts: true
+      failed_when: false
+      changed_when: false
+      no_log: true
+
+    - name: Assert the ESXi placement host is readable
+      when: hypervisor_cfg.node | default('') | length > 0
+      ansible.builtin.assert:
+        that:
+          - system_check_esxi.ansible_facts is defined
+        fail_msg: |
+          ESXi host {{ hypervisor_cfg.node }} (hypervisor.node) could not be read from vCenter {{ hypervisor_cfg.url }}.
+          {{ system_check_esxi.msg | default('Unknown error') }}
+          Set hypervisor.node to an ESXi host in datacenter {{ hypervisor_cfg.datacenter }},
+          or clear hypervisor.node and set hypervisor.cluster instead.
+        quiet: true
+
+    - name: Assert the ESXi placement host can take a new VM
+      when: hypervisor_cfg.node | default('') | length > 0
+      ansible.builtin.assert:
+        that:
+          - system_check_esxi.ansible_facts.ansible_host_connection_state == "connected"
+          - not (system_check_esxi.ansible_facts.ansible_in_maintenance_mode | bool)
+        fail_msg: |
+          ESXi host {{ hypervisor_cfg.node }} (hypervisor.node) cannot take a new VM:
+          connection state is {{ system_check_esxi.ansible_facts.ansible_host_connection_state }},
+          maintenance mode is {{ system_check_esxi.ansible_facts.ansible_in_maintenance_mode }}.
+          Wait for the host to come back, or set hypervisor.node to another host.
+        quiet: true
+
+    - name: Query the datastores of the placement cluster
+      when: hypervisor_cfg.node | default('') | length == 0
+      community.vmware.vmware_datastore_info:
+        cluster: "{{ hypervisor_cfg.cluster }}"
+      register: system_check_cluster
+      failed_when: false
+      changed_when: false
+      no_log: true
+
+    - name: Assert the placement cluster is readable
+      when: hypervisor_cfg.node | default('') | length == 0
+      ansible.builtin.assert:
+        that:
+          - system_check_cluster.datastores is defined
+        fail_msg: |
+          Cluster {{ hypervisor_cfg.cluster }} (hypervisor.cluster) could not be read from vCenter {{ hypervisor_cfg.url }}.
+          {{ system_check_cluster.msg | default('Unknown error') }}
+          Set hypervisor.cluster to a cluster in datacenter {{ hypervisor_cfg.datacenter }},
+          or clear hypervisor.cluster and pin hypervisor.node instead.
+        quiet: true
+
+    - name: Resolve the datastores available at the placement target
+      ansible.builtin.set_fact:
+        system_check_target: >-
+          {{ ('ESXi host ' ~ hypervisor_cfg.node ~ ' (hypervisor.node)')
+             if (hypervisor_cfg.node | default('') | length > 0)
+             else ('cluster ' ~ hypervisor_cfg.cluster ~ ' (hypervisor.cluster)') }}
+        system_check_datastores_available: >-
+          {{ (system_check_esxi.ansible_facts.ansible_datastore | map(attribute='name') | list)
+             if (hypervisor_cfg.node | default('') | length > 0)
+             else (system_check_cluster.datastores | map(attribute='name') | list) }}
+
+    - name: Assert every datastore this run needs is available at the placement target
+      ansible.builtin.assert:
+        that:
+          - item.datastore in system_check_datastores_available
+        fail_msg: |
+          Datastore {{ item.datastore }} (from {{ item.source }}) is not available on {{ system_check_target }}.
+          Datastores available there: {{ system_check_datastores_available | join(', ') }}.
+          Point {{ item.source }} at one of those datastores, or move placement to a host or cluster
+          that mounts {{ item.datastore }}.
+        quiet: true
+      loop: "{{ system_check_datastores_needed }}"
+      loop_control:
+        label: "{{ item.source }}: {{ item.datastore }}"
+
+    - name: Query the boot media on its datastore
+      community.vmware.vsphere_file:
+        datacenter: "{{ hypervisor_cfg.datacenter }}"
+        datastore: "{{ item.datastore }}"
+        path: "{{ item.path }}"
+        state: file
+      register: system_check_media_files
+      failed_when: false
+      changed_when: false
+      loop: "{{ system_check_datastores_needed | rejectattr('source', 'equalto', 'hypervisor.storage') | list }}"
+      loop_control:
+        label: "{{ item.source }}"
+
+    - name: Assert the boot media exists on its datastore
+      ansible.builtin.assert:
+        that:
+          - (item.status | default(0)) != 404
+        fail_msg: |
+          {{ item.item.source }} points at "[{{ item.item.datastore }}] {{ item.item.path }}",
+          which does not exist on datastore {{ item.item.datastore }}.
+          Set {{ item.item.source }} to a file that exists there, normally the current SGBoot ISO.
+        quiet: true
+      loop: "{{ system_check_media_files.results }}"
+      loop_control:
+        label: "{{ item.item.source }}"
+
+- name: Verify Proxmox boot media
+  when: hypervisor_type == "proxmox"
+  delegate_to: localhost
+  become: false
+  module_defaults:
+    community.proxmox.proxmox_storage_contents_info:
+      api_host: "{{ hypervisor_cfg.url }}"
+      api_user: "{{ hypervisor_cfg.username }}"
+      api_password: "{{ hypervisor_cfg.password | default(omit, true) }}"
+      api_token_id: "{{ hypervisor_cfg.token_id | default(omit, true) }}"
+      api_token_secret: "{{ hypervisor_cfg.token_secret | default(omit, true) }}"
+  block:
+    - name: Assert the boot media is a storage volume id
+      ansible.builtin.assert:
+        that:
+          - item.value is match('^[^:]+:iso/\\S')
+        fail_msg: |
+          {{ item.name }} is "{{ item.value }}", which is not a Proxmox volume id.
+          Set {{ item.name }} to the form "<storage>:iso/<file>.iso",
+          for example "local:iso/SGBoot-2026.06.09-x86_64.iso".
+        quiet: true
+      loop: "{{ system_check_media }}"
+      loop_control:
+        label: "{{ item.name }}"
+
+    - name: Query the ISO volumes on the Proxmox node
+      community.proxmox.proxmox_storage_contents_info:
+        node: "{{ hypervisor_cfg.node }}"
+        storage: "{{ item.value | regex_replace('^([^:]+):.*$', '\\1') }}"
+        content: iso
+      register: system_check_proxmox_media
+      failed_when: false
+      changed_when: false
+      loop: "{{ system_check_media }}"
+      loop_control:
+        label: "{{ item.name }}"
+
+    - name: Assert the boot media storage serves ISOs on the Proxmox node
+      ansible.builtin.assert:
+        that:
+          - item.proxmox_storage_content is defined
+        fail_msg: |
+          Storage {{ item.item.value | regex_replace('^([^:]+):.*$', '\\1') }} (from {{ item.item.name }})
+          does not serve ISO content on Proxmox node {{ hypervisor_cfg.node }}.
+          {{ item.msg | default('Unknown error') }}
+          Point {{ item.item.name }} at a storage that is enabled for ISO images on that node,
+          or change hypervisor.node.
+        quiet: true
+      loop: "{{ system_check_proxmox_media.results }}"
+      loop_control:
+        label: "{{ item.item.name }}"
+
+    - name: Assert the boot media exists on the Proxmox node
+      ansible.builtin.assert:
+        that:
+          - item.item.value in (item.proxmox_storage_content | map(attribute='volid') | list)
+        fail_msg: |
+          {{ item.item.name }} points at "{{ item.item.value }}", which does not exist on Proxmox node
+          {{ hypervisor_cfg.node }}.
+          ISO volumes on that storage: {{ item.proxmox_storage_content | map(attribute='volid') | join(', ') }}.
+          Set {{ item.item.name }} to one of those volumes.
+        quiet: true
+      loop: "{{ system_check_proxmox_media.results }}"
+      loop_control:
+        label: "{{ item.item.name }}"
+
+- name: Verify libvirt boot media
+  when: hypervisor_type == "libvirt"
+  delegate_to: localhost
+  become: false
+  block:
+    - name: Stat the libvirt boot media
+      ansible.builtin.stat:
+        path: "{{ item.value }}"
+      register: system_check_libvirt_media
+      loop: "{{ system_check_media }}"
+      loop_control:
+        label: "{{ item.name }}"
+
+    - name: Assert the libvirt boot media exists
+      ansible.builtin.assert:
+        that:
+          - item.stat.exists
+        fail_msg: |
+          {{ item.item.name }} points at "{{ item.item.value }}", which does not exist on the libvirt host.
+          Set {{ item.item.name }} to the path of an ISO file that exists there.
+        quiet: true
+      loop: "{{ system_check_libvirt_media.results }}"
+      loop_control:
+        label: "{{ item.item.name }}"
diff --git a/roles/system_check/tasks/main.yml b/roles/system_check/tasks/main.yml
index 303eb75..95a7b6a 100644
--- a/roles/system_check/tasks/main.yml
+++ b/roles/system_check/tasks/main.yml
@@ -132,3 +132,7 @@
           To avoid data loss, the playbook will not overwrite or delete existing VMs.
           Please choose a different hostname or remove the existing VM manually before proceeding.
         quiet: true
+
+- name: Verify boot media and placement target
+  when: system_cfg.type == "virtual"
+  ansible.builtin.include_tasks: _placement.yml