Check if mountpoint is already mounted beforehand for tls mount

README.md

@@ -15,10 +15,14 @@ The `efs-utils` package has been verified against the following Linux distributi
 | RHEL 8 | `rpm`| `systemd` |
 | Fedora 28 | `rpm` | `systemd` |
 | Fedora 29 | `rpm` | `systemd` |
+| Fedora 30 | `rpm` | `systemd` |
+| Fedora 31 | `rpm` | `systemd` |
+| Fedora 32 | `rpm` | `systemd` |
 | Debian 9 | `deb` | `systemd` |
 | Debian 10 | `deb` | `systemd` |
 | Ubuntu 16.04 | `deb` | `systemd` |
 | Ubuntu 18.04 | `deb` | `systemd` |
+| Ubuntu 20.04 | `deb` | `systemd` |
 
 ## Prerequisites
 

dist/amazon-efs-utils.spec

@@ -130,6 +130,7 @@ fi
 - Fix an issue where subprocess was not killed successfully
 - Stop emitting unrecognized init system supervisord if the watchdog daemon has already been launched by supervisor
 - Support Fedora
+- Check if mountpoint is already mounted beforehand for tls mount
 
 * Tue May 05 2020 Yuan Gao <ygaochn@amazon.com> - 1.25-2
 - Fix the issue that IAM role name format is not correctly encoded in python3

src/mount_efs/__init__.py

@@ -1490,6 +1490,11 @@ def match_device(config, device):
 
 
 def mount_tls(config, init_system, dns_name, path, fs_id, mountpoint, options):
+    if os.path.ismount(mountpoint):
+        sys.stdout.write("%s is already mounted, please run 'mount' command to verify\n" % mountpoint)
+        logging.warn("%s is already mounted, mount aborted" % mountpoint)
+        return
+
     with bootstrap_tls(config, init_system, dns_name, fs_id, mountpoint, options) as tunnel_proc:
         mount_completed = threading.Event()
         t = threading.Thread(target=poll_tunnel_process, args=(tunnel_proc, fs_id, mount_completed))

test/mount_efs_test/test_mount_nfs.py

@@ -11,8 +11,14 @@ import mount_efs
 import pytest
 
 from mock import MagicMock
+from .. import utils
 
+CONFIG = MagicMock()
 DNS_NAME = 'fs-deadbeef.efs.us-east-1.amazonaws.com'
+FS_ID = 'fs-deadbeef'
+INIT_SYSTEM = 'upstart'
+MOUNT_POINT = '/mnt'
+PATH = '/'
 
 DEFAULT_OPTIONS = {'nfsvers': 4.1, 'rsize': 1048576, 'wsize': 1048576, 'hard': None, 'timeo': 600, 'retrans': 2, 'tlsport': 3049}
 
@@ -93,4 +99,16 @@ def test_mount_nfs_tls_netns(mocker):
     assert '/sbin/mount.nfs4' == args[NFS_BIN_ARG_IDX + NETNS_NFS_OFFSET]
     assert DNS_NAME not in args[NFS_MOUNT_PATH_IDX + NETNS_NFS_OFFSET]
     assert '127.0.0.1' in args[NFS_MOUNT_PATH_IDX + NETNS_NFS_OFFSET]
-    assert '/mnt' in args[NFS_MOUNT_POINT_IDX + NETNS_NFS_OFFSET]
\ No newline at end of file
+    assert '/mnt' in args[NFS_MOUNT_POINT_IDX + NETNS_NFS_OFFSET]
+
+
+def test_mount_tls_mountpoint_mounted(mocker, capsys):
+    options = dict(DEFAULT_OPTIONS)
+    options['tls'] = None
+
+    bootstrap_tls_mock = mocker.patch('mount_efs.bootstrap_tls')
+    mocker.patch('os.path.ismount', return_value=True)
+    mount_efs.mount_tls(CONFIG, INIT_SYSTEM, DNS_NAME, PATH, FS_ID, MOUNT_POINT, options)
+    out, err = capsys.readouterr()
+    assert 'is already mounted' in out
+    utils.assert_not_called(bootstrap_tls_mock)