From f05afa4813f425e9fc9960f63100431a78310638 Mon Sep 17 00:00:00 2001
From: Alexander Bokovoy <abokovoy@redhat.com>
Date: Sep 20 2017 10:56:42 +0000
Subject: Make sure upgrade also checks for IPv6 stack


 - Add check for IPv6 stack to upgrade process
 - Change IPv6 checker to also check that localhost resolves to ::1

Part of fixes https://pagure.io/freeipa/issue/7083

Reviewed-By: Tomas Krizek <tkrizek@redhat.com>

---

diff --git a/ipaplatform/redhat/tasks.py b/ipaplatform/redhat/tasks.py
index e3bb127..81c9286 100644
--- a/ipaplatform/redhat/tasks.py
+++ b/ipaplatform/redhat/tasks.py
@@ -146,9 +146,22 @@ class RedHatTaskNamespace(BaseTaskNamespace):
         """
         if not os.path.exists(paths.IF_INET6):
             raise RuntimeError(
-                "IPv6 kernel module has to be enabled. If you do not wish to "
-                "use IPv6, please disable it on the interfaces in "
-                "sysctl.conf and enable the IPv6 kernel module.")
+                "IPv6 stack has to be enabled in the kernel and some "
+                "interface has to have ::1 address assigned. Typically "
+                "this is 'lo' interface. If you do not wish to use IPv6 "
+                "globally, disable it on the specific interfaces in "
+                "sysctl.conf except 'lo' interface.")
+
+        try:
+            localhost6 = ipautil.CheckedIPAddress('::1', allow_loopback=True)
+            if localhost6.get_matching_interface() is None:
+                raise ValueError("no interface for ::1 address found")
+        except ValueError:
+            raise RuntimeError(
+                 "IPv6 stack is enabled in the kernel but there is no "
+                 "interface that has ::1 address assigned. Add ::1 address "
+                 "resolution to 'lo' interface. You might need to enable IPv6 "
+                 "on the interface 'lo' in sysctl.conf.")
 
     def restore_pre_ipa_client_configuration(self, fstore, statestore,
                                              was_sssd_installed,
diff --git a/ipaserver/install/server/upgrade.py b/ipaserver/install/server/upgrade.py
index a3a2864..06e1886 100644
--- a/ipaserver/install/server/upgrade.py
+++ b/ipaserver/install/server/upgrade.py
@@ -1908,6 +1908,7 @@ def upgrade_configuration():
 def upgrade_check(options):
     try:
         installutils.check_server_configuration()
+        tasks.check_ipv6_stack_enabled()
     except RuntimeError as e:
         logger.error("%s", e)
         sys.exit(1)