diff --git a/bin/sau b/bin/sau
index 9fba187..77db1fc 100755
--- a/bin/sau
+++ b/bin/sau
@@ -8,6 +8,7 @@ import sys
 import time
 
 import sau
+import sau.errors
 import sau.services
 import sau.platforms
 
@@ -101,11 +102,15 @@ def main():
     reboot_required = False
     reboot_recommended = False
 
-    if conf.getboolean('default', 'do_system_upgrade', fallback=True):
-        reboot_required = platform.system_upgrade()
+    try:
+        if conf.getboolean('default', 'do_system_upgrade', fallback=True):
+            reboot_required = platform.system_upgrade()
 
-    if conf.getboolean('default', 'do_package_upgrade', fallback=True):
-        reboot_required = reboot_required or platform.pkg_upgrade()
+        if conf.getboolean('default', 'do_package_upgrade', fallback=True):
+            reboot_required = reboot_required or platform.pkg_upgrade()
+    except sau.errors.UpgradeError as e:
+        log.error(f'Upgrade failed: {e}')
+        return 1
 
     if conf.getboolean('default', 'do_service_restart', fallback=True):
         reboot_recommended = sau.services.restart_services()
@@ -118,6 +123,7 @@ def main():
         if reboot_required or reboot_recommended:
             fork_and_reboot()
 
+
 def _conf_level_to_logging_level(conf_level):
     if conf_level.lower() == 'debug':
         return logging.DEBUG
diff --git a/sau/__init__.py b/sau/__init__.py
index 1f34017..b768835 100644
--- a/sau/__init__.py
+++ b/sau/__init__.py
@@ -1,2 +1 @@
-
 LOGNAME="sau"
diff --git a/sau/errors.py b/sau/errors.py
index 993af60..665a350 100644
--- a/sau/errors.py
+++ b/sau/errors.py
@@ -5,3 +5,5 @@ class PlatformNotSupported(Exception):
 class UnknownServiceError(Exception):
     pass
 
+class UpgradeError(Exception):
+    pass
diff --git a/sau/gentoo.py b/sau/gentoo.py
index e77d52e..86742a6 100644
--- a/sau/gentoo.py
+++ b/sau/gentoo.py
@@ -92,11 +92,12 @@ def _sync_portage():
         ret, out, err = sau.helpers.exec_cmd(cmd, timeout=3600)
 
     if ret != 0:
-        log.warning("Portage sync failed:")
+        log.error("Portage sync failed:")
         for line in out.splitlines():
-            log.warning("stdout: {}".format(line))
+            log.error("stdout: {}".format(line))
         for line in err.splitlines():
-            log.warning("stderr: {}".format(line))
+            log.error("stderr: {}".format(line))
+        raise sau.errors.UpgradeError(f'Sync command {cmd} failed')
 
     cmd = [ EMAINT_PATH, '-f', 'all' ]
     ret, out, err = sau.helpers.exec_cmd(cmd, timeout=3600)
@@ -134,7 +135,7 @@ def pkg_upgrade():
             log.error('stdout: {}'.format(line))
         for line in err.splitlines():
             log.error('stderr: {}'.format(line))
-        return False
+        raise sau.errors.UpgradeError(f'Failed to calculate upgrade path')
 
     do_rebuild = True
     do_grub = False
@@ -164,22 +165,21 @@ def pkg_upgrade():
             if do_system_upgrade:
                 do_grub = True
             else:
-                log.warning(f"Kernel package {name} has an update, but system upgrade is disabled")
-                do_rebuild = False
+                raise sau.errors.UpgradeError(f"Kernel package {name} has an update, but system upgrade is disabled")
 
     if not do_rebuild:
-        log.warning('Some packages require manual attention, did not upgrade')
-        return False
+        sau.errors.UpgradeError('Some packages require manual attention, did not upgrade')
 
     cmd = [ EMERGE_PATH, '--color', 'n', '-uDNq', '--with-bdeps=y', '@world' ]
     ret, out, err = sau.helpers.exec_cmd(cmd, timeout=72000)
 
     if ret != 0 or err:
-        log.warning('emerge returned {}'.format(ret))
+        log.error('emerge returned {}'.format(ret))
         for line in out.splitlines():
-            log.warning('stdout: {}'.format(line))
+            log.error('stdout: {}'.format(line))
         for line in err.splitlines():
-            log.warning('stderr: {}'.format(line))
+            log.error('stderr: {}'.format(line))
+        raise sau.errors.UpgradeError(f'Error during upgrade')
     else:
         log.info('upgrade complete')
         for line in out.splitlines():
@@ -190,11 +190,12 @@ def pkg_upgrade():
     ret, out, err = sau.helpers.exec_cmd(cmd, timeout=72000)
 
     if ret != 0 or err:
-        log.warning('preserved-rebuild returned {}'.format(ret))
+        log.error('preserved-rebuild returned {}'.format(ret))
         for line in out.splitlines():
-            log.warning('stdout: {}'.format(line))
+            log.error('stdout: {}'.format(line))
         for line in err.splitlines():
-            log.warning('stderr: {}'.format(line))
+            log.error('stderr: {}'.format(line))
+        raise sau.errors.UpgradeError(f'Error during preserved-rebuild')
     else:
         log.info('preserved-rebuild complete')
         for line in out.splitlines():
@@ -205,11 +206,12 @@ def pkg_upgrade():
         cmd = [ EMERGE_PATH, '--color', 'n', '-q', '--depclean' ]
         ret, out, err = sau.helpers.exec_cmd(cmd, timeout=3600)
         if ret != 0 or err:
-            log.warning('depclean returned {}'.format(ret))
+            log.error('depclean returned {}'.format(ret))
             for line in out.splitlines():
-                log.warning('stdout: {}'.format(line))
+                log.error('stdout: {}'.format(line))
             for line in err.splitlines():
-                log.warning('stderr: {}'.format(line))
+                log.error('stderr: {}'.format(line))
+            raise sau.errors.UpgradeError(f'Error during depclean')
         else:
             log.info('depclean complete')
             for line in out.splitlines():
@@ -234,11 +236,12 @@ def pkg_upgrade():
         cmd = [ GRUB_MKCONFIG, '-o', '/boot/grub/grub.cfg' ]
         ret, out, err = sau.helpers.exec_cmd(cmd)
         if ret != 0:
-            log.warning(f"grub-mkconfig returned {ret}:")
+            log.error(f"grub-mkconfig returned {ret}:")
             for line in out.splitlines():
-                log.warning('stdout: {}'.format(line))
+                log.error('stdout: {}'.format(line))
             for line in err.splitlines():
-                log.warning('stderr: {}'.format(line))
+                log.error('stderr: {}'.format(line))
+            raise sau.errors.UpgradeError(f'Failed to reconfiugre grub')
         else:
             log.info("grub reconfigured")
             return True