From 3c875aa98bc2329b3cbca763af17a9a7cbc3921b Mon Sep 17 00:00:00 2001
From: Adam King <adking@redhat.com>
Date: Mon, 28 Feb 2022 20:23:10 -0500
Subject: [PATCH] mgr/cephadm: block removing last instance of _admin label

Fixes: https://tracker.ceph.com/issues/54425

Signed-off-by: Adam King <adking@redhat.com>
(cherry picked from commit fbe0c3fd23f9005986959bade149093c340f6238)

Conflicts:
	src/pybind/mgr/rook/module.py
---
 src/pybind/mgr/cephadm/module.py          | 14 +++++++++++++-
 src/pybind/mgr/orchestrator/_interface.py |  2 +-
 src/pybind/mgr/orchestrator/module.py     |  4 ++--
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/pybind/mgr/cephadm/module.py b/src/pybind/mgr/cephadm/module.py
index 13b5040ed98bc..a6ad4f84d4170 100644
--- a/src/pybind/mgr/cephadm/module.py
+++ b/src/pybind/mgr/cephadm/module.py
@@ -1651,7 +1651,19 @@ Then run the following:
         return 'Added label %s to host %s' % (label, host)
 
     @handle_orch_error
-    def remove_host_label(self, host: str, label: str) -> str:
+    def remove_host_label(self, host: str, label: str, force: bool = False) -> str:
+        # if we remove the _admin label from the only host that has it we could end up
+        # removing the only instance of the config and keyring and cause issues
+        if not force and label == '_admin':
+            p = PlacementSpec(label='_admin')
+            admin_hosts = p.filter_matching_hostspecs(self.inventory.all_specs())
+            if len(admin_hosts) == 1 and admin_hosts[0] == host:
+                raise OrchestratorValidationError(f"Host {host} is the last host with the '_admin'"
+                                                  " label.\nRemoving the _admin label from this host could cause the removal"
+                                                  " of the last cluster config/keyring managed by cephadm.\n"
+                                                  "It is recommended to add the _admin label to another host"
+                                                  " before completing this operation.\nIf you're certain this is"
+                                                  " what you want rerun this command with --force.")
         self.inventory.rm_label(host, label)
         self.log.info('Removed label %s to host %s' % (label, host))
         self._kick_serve_loop()
diff --git a/src/pybind/mgr/orchestrator/_interface.py b/src/pybind/mgr/orchestrator/_interface.py
index a1b1893db0cdf..69c04acd83d41 100644
--- a/src/pybind/mgr/orchestrator/_interface.py
+++ b/src/pybind/mgr/orchestrator/_interface.py
@@ -392,7 +392,7 @@ class Orchestrator(object):
         """
         raise NotImplementedError()
 
-    def remove_host_label(self, host: str, label: str) -> OrchResult[str]:
+    def remove_host_label(self, host: str, label: str, force: bool = False) -> OrchResult[str]:
         """
         Remove a host label
         """
diff --git a/src/pybind/mgr/orchestrator/module.py b/src/pybind/mgr/orchestrator/module.py
index 10381db9c14a7..340710eb8cc58 100644
--- a/src/pybind/mgr/orchestrator/module.py
+++ b/src/pybind/mgr/orchestrator/module.py
@@ -418,9 +418,9 @@ class OrchestratorCli(OrchestratorClientMixin, MgrModule,
         return HandleCommandResult(stdout=completion.result_str())
 
     @_cli_write_command('orch host label rm')
-    def _host_label_rm(self, hostname: str, label: str) -> HandleCommandResult:
+    def _host_label_rm(self, hostname: str, label: str, force: bool = False) -> HandleCommandResult:
         """Remove a host label"""
-        completion = self.remove_host_label(hostname, label)
+        completion = self.remove_host_label(hostname, label, force)
         raise_if_exception(completion)
         return HandleCommandResult(stdout=completion.result_str())
 
-- 
2.39.5