diff --git a/hathor/sysctl/runner.py b/hathor/sysctl/runner.py
index ef75a21b6..eb948e6f7 100644
--- a/hathor/sysctl/runner.py
+++ b/hathor/sysctl/runner.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 
 import json
+import re
 from typing import TYPE_CHECKING, Any
 
 from hathor.sysctl.exception import SysctlRunnerException
@@ -20,6 +21,22 @@
 if TYPE_CHECKING:
     from hathor.sysctl.sysctl import Sysctl
 
+# Top level:
+# - Allow numbers, integers and float
+# - Allow string in double quote
+# - Allow mix of numbers with strings
+# - Allow space before, after and between elements
+# - Don't allow empty element like [1,,2]; empty element between 1 and 2
+# - Don't allow comma (,) after last element
+# - Don't allow double quote (") inside string
+# Regex:
+# - \[ - start list
+# - ]] - end list
+# - \s* - accept space in any quantity
+# - \d+ - accept at least 1 number
+# - ^" - negate double quote
+array_pattern = r'\[(?:\s*(\d+\.\d+|\s*\d+)\s*|\s*"([^"]*)"\s*)(?:,\s*(\d+\.\d+|\s*\d+)\s*|,\s*"([^"]*)"\s*)*\]|\[\]'
+
 
 class SysctlRunner:
     """ Encapsulates the Sysctl to decouple it from the SyctlProtocol.
@@ -76,6 +93,9 @@ def deserialize(self, value_str: str) -> Any:
         if len(value_str) == 0:
             return ()
 
+        if re.match(array_pattern, value_str):
+            return list(json.loads(value_str))
+
         parts = [x.strip() for x in value_str.split(',')]
         if len(parts) > 1:
             return tuple(json.loads(x) for x in parts)
diff --git a/tests/cli/test_sysctl_init.py b/tests/cli/test_sysctl_init.py
index a696e2008..d3241723e 100644
--- a/tests/cli/test_sysctl_init.py
+++ b/tests/cli/test_sysctl_init.py
@@ -113,12 +113,14 @@ def register_signal_handlers(self) -> None:
             'p2p.max_enabled_sync': 7,
             'p2p.rate_limit.global.send_tips': (5, 3),
             'p2p.sync_update_interval': 17,
+            'p2p.always_enable_sync': ['peer-1', 'peer-2'],
         }
 
         file_content = [
             'p2p.max_enabled_sync=7',
             'p2p.rate_limit.global.send_tips=5,3',
             'p2p.sync_update_interval=17',
+            'p2p.always_enable_sync=["peer-1","peer-2"]',
         ]
 
         with tempfile.NamedTemporaryFile(
@@ -155,6 +157,10 @@ def register_signal_handlers(self) -> None:
                 curr_sync_update_interval,
                 expected_sysctl_dict['p2p.sync_update_interval'])
 
+        curr_always_enabled_sync = list(conn.always_enable_sync)
+        self.assertTrue(
+                set(curr_always_enabled_sync).issuperset(set(expected_sysctl_dict['p2p.always_enable_sync'])))
+
         # assert always_enabled_sync when it is set with a file
         expected_sysctl_dict = {
             'p2p.always_enable_sync': ['peer-3', 'peer-4'],
@@ -198,3 +204,36 @@ def register_signal_handlers(self) -> None:
         curr_always_enabled_sync = list(conn.always_enable_sync)
         self.assertTrue(
                 set(curr_always_enabled_sync).issuperset(set(expected_sysctl_dict['p2p.always_enable_sync'])))
+
+    @patch('twisted.internet.endpoints.serverFromString')  # avoid open sock
+    def test_sysctl_init_file_failing_list_parsing(self, mock_endpoint):
+        class CustomRunNode(RunNode):
+            def start_manager(self) -> None:
+                pass
+
+            def register_signal_handlers(self) -> None:
+                pass
+
+        test_cases = [
+            ['p2p.always_enable_sync=[ "peer-1", "peer-2", ]'],
+            ['p2p.always_enable_sync=["peer-1",,"peer-2"]'],
+            ['p2p.always_enable_sync=["peer-1","\"peer-2\""]'],
+            ['p2p.always_enable_sync=[1,2,]'],
+            ['p2p.always_enable_sync=[1,,2]']
+        ]
+
+        for file_content in test_cases:
+            with tempfile.NamedTemporaryFile(
+                    dir=self.tmp_dir,
+                    suffix='.txt',
+                    prefix='sysctl_',
+                    delete=False) as sysctl_init_file:
+                sysctl_init_file.write('\n'.join(file_content).encode())
+                sysctl_init_file_path = str(Path(sysctl_init_file.name))
+
+            with self.assertRaises(SysctlRunnerException):
+                CustomRunNode(argv=[
+                    '--sysctl', 'tcp:8181',
+                    '--sysctl-init-file', sysctl_init_file_path,  # relative to src/hathor
+                    '--memory-storage',
+                ])