diff --git a/test/py/tests/fs_helper.py b/test/py/tests/fs_helper.py
index ccfc020..378d5ae 100644
--- a/test/py/tests/fs_helper.py
+++ b/test/py/tests/fs_helper.py
@@ -35,7 +35,7 @@
     else:
         mkfs_opt = ''
 
-    if re.match('fat', fs_type):
+    if re.match('fat', fs_type) or fs_type == 'fs_generic':
         fs_lnxtype = 'vfat'
     else:
         fs_lnxtype = fs_type
diff --git a/test/py/tests/test_fs/conftest.py b/test/py/tests/test_fs/conftest.py
index 47a584f..691bdf4 100644
--- a/test/py/tests/test_fs/conftest.py
+++ b/test/py/tests/test_fs/conftest.py
@@ -11,11 +11,11 @@
 # pylint: disable=E0611
 from tests import fs_helper
 
-supported_fs_basic = ['fat16', 'fat32', 'ext4']
-supported_fs_ext = ['fat12', 'fat16', 'fat32']
+supported_fs_basic = ['fat16', 'fat32', 'ext4', 'fs_generic']
+supported_fs_ext = ['fat12', 'fat16', 'fat32', 'fs_generic']
 supported_fs_fat = ['fat12', 'fat16']
-supported_fs_mkdir = ['fat12', 'fat16', 'fat32']
-supported_fs_unlink = ['fat12', 'fat16', 'fat32']
+supported_fs_mkdir = ['fat12', 'fat16', 'fat32', 'fs_generic']
+supported_fs_unlink = ['fat12', 'fat16', 'fat32', 'fs_generic']
 supported_fs_symlink = ['ext4']
 supported_fs_rename = ['fat12', 'fat16', 'fat32']
 
@@ -108,6 +108,22 @@
 #
 # Helper functions
 #
+def fstype_to_prefix(fs_type):
+    """Convert a file system type to an U-Boot command prefix
+
+    Args:
+        fs_type: File system type.
+
+    Return:
+        A corresponding command prefix for file system type.
+    """
+    if fs_type == 'fs_generic':
+        return ''
+    elif re.match('fat', fs_type):
+        return 'fat'
+    else:
+        return fs_type
+
 def fstype_to_ubname(fs_type):
     """Convert a file system type to an U-Boot specific string
 
@@ -141,6 +157,8 @@
     """
     if not config.buildconfig.get('config_cmd_%s' % fs_type, None):
         pytest.skip('.config feature "CMD_%s" not enabled' % fs_type.upper())
+    if fs_type == 'fs_generic':
+        return
     if not config.buildconfig.get('config_%s_write' % fs_type, None):
         pytest.skip('.config feature "%s_WRITE" not enabled'
         % fs_type.upper())
@@ -178,6 +196,8 @@
         volume file name and  a list of MD5 hashes.
     """
     fs_type = request.param
+    fs_cmd_prefix = fstype_to_prefix(fs_type)
+    fs_cmd_write = 'save' if fs_type == 'fs_generic' else 'write'
     fs_img = ''
 
     fs_ubtype = fstype_to_ubname(fs_type)
@@ -267,7 +287,7 @@
         pytest.skip('Setup failed for filesystem: ' + fs_type + '. {}'.format(err))
         return
     else:
-        yield [fs_ubtype, fs_img, md5val]
+        yield [fs_ubtype, fs_cmd_prefix, fs_cmd_write, fs_img, md5val]
     finally:
         call('rm -rf %s' % scratch_dir, shell=True)
         call('rm -f %s' % fs_img, shell=True)
@@ -288,6 +308,8 @@
         volume file name and  a list of MD5 hashes.
     """
     fs_type = request.param
+    fs_cmd_prefix = fstype_to_prefix(fs_type)
+    fs_cmd_write = 'save' if fs_type == 'fs_generic' else 'write'
     fs_img = ''
 
     fs_ubtype = fstype_to_ubname(fs_type)
@@ -357,7 +379,7 @@
         pytest.skip('Setup failed for filesystem: ' + fs_type)
         return
     else:
-        yield [fs_ubtype, fs_img, md5val]
+        yield [fs_ubtype, fs_cmd_prefix, fs_cmd_write, fs_img, md5val]
     finally:
         call('rm -rf %s' % scratch_dir, shell=True)
         call('rm -f %s' % fs_img, shell=True)
@@ -378,6 +400,7 @@
         volume file name.
     """
     fs_type = request.param
+    fs_cmd_prefix = fstype_to_prefix(fs_type)
     fs_img = ''
 
     fs_ubtype = fstype_to_ubname(fs_type)
@@ -390,7 +413,7 @@
         pytest.skip('Setup failed for filesystem: ' + fs_type)
         return
     else:
-        yield [fs_ubtype, fs_img]
+        yield [fs_ubtype, fs_cmd_prefix, fs_img]
     call('rm -f %s' % fs_img, shell=True)
 
 #
@@ -409,6 +432,7 @@
         volume file name.
     """
     fs_type = request.param
+    fs_cmd_prefix = fstype_to_prefix(fs_type)
     fs_img = ''
 
     fs_ubtype = fstype_to_ubname(fs_type)
@@ -456,7 +480,7 @@
         pytest.skip('Setup failed for filesystem: ' + fs_type)
         return
     else:
-        yield [fs_ubtype, fs_img]
+        yield [fs_ubtype, fs_cmd_prefix, fs_img]
     finally:
         call('rm -rf %s' % scratch_dir, shell=True)
         call('rm -f %s' % fs_img, shell=True)
diff --git a/test/py/tests/test_fs/test_basic.py b/test/py/tests/test_fs/test_basic.py
index 5a02348..64a3b50 100644
--- a/test/py/tests/test_fs/test_basic.py
+++ b/test/py/tests/test_fs/test_basic.py
@@ -20,32 +20,32 @@
         """
         Test Case 1 - ls command, listing a root directory and invalid directory
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 1a - ls'):
             # Test Case 1 - ls
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sls host 0:0' % fs_type])
+                '%sls host 0:0' % fs_cmd_prefix])
             assert(re.search('2621440000 *%s' % BIG_FILE, ''.join(output)))
             assert(re.search('1048576 *%s' % SMALL_FILE, ''.join(output)))
 
         with ubman.log.section('Test Case 1b - ls (invalid dir)'):
             # In addition, test with a nonexistent directory to see if we crash.
             output = ubman.run_command(
-                '%sls host 0:0 invalid_d' % fs_type)
+                '%sls host 0:0 invalid_d' % fs_cmd_prefix)
             assert('' == output)
 
     def test_fs2(self, ubman, fs_obj_basic):
         """
         Test Case 2 - size command for a small file
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 2a - size (small)'):
             # 1MB is 0x0010 0000
             # Test Case 2a - size of small file
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%ssize host 0:0 /%s' % (fs_type, SMALL_FILE),
+                '%ssize host 0:0 /%s' % (fs_cmd_prefix, SMALL_FILE),
                 'printenv filesize',
                 'setenv filesize'])
             assert('filesize=100000' in ''.join(output))
@@ -53,7 +53,7 @@
         with ubman.log.section('Test Case 2b - size (/../<file>)'):
             # Test Case 2b - size of small file via a path using '..'
             output = ubman.run_command_list([
-                '%ssize host 0:0 /SUBDIR/../%s' % (fs_type, SMALL_FILE),
+                '%ssize host 0:0 /SUBDIR/../%s' % (fs_cmd_prefix, SMALL_FILE),
                 'printenv filesize',
                 'setenv filesize'])
             assert('filesize=100000' in ''.join(output))
@@ -62,13 +62,13 @@
         """
         Test Case 3 - size command for a large file
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 3 - size (large)'):
             # 2.5GB (1024*1024*2500) is 0x9C40 0000
             # Test Case 3 - size of big file
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%ssize host 0:0 /%s' % (fs_type, BIG_FILE),
+                '%ssize host 0:0 /%s' % (fs_cmd_prefix, BIG_FILE),
                 'printenv filesize',
                 'setenv filesize'])
             assert('filesize=9c400000' in ''.join(output))
@@ -77,12 +77,12 @@
         """
         Test Case 4 - load a small file, 1MB
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 4 - load (small)'):
             # Test Case 4a - Read full 1MB of small file
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, SMALL_FILE),
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, SMALL_FILE),
                 'printenv filesize'])
             assert('filesize=100000' in ''.join(output))
 
@@ -96,12 +96,12 @@
         """
         Test Case 5 - load, reading first 1MB of 3GB file
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 5 - load (first 1MB)'):
             # Test Case 5a - First 1MB of big file
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s %x 0x0' % (fs_type, ADDR, BIG_FILE, LENGTH),
+                '%sload host 0:0 %x /%s %x 0x0' % (fs_cmd_prefix, ADDR, BIG_FILE, LENGTH),
                 'printenv filesize'])
             assert('filesize=100000' in ''.join(output))
 
@@ -115,14 +115,14 @@
         """
         Test Case 6 - load, reading last 1MB of 3GB file
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 6 - load (last 1MB)'):
             # fails for ext as no offset support
             # Test Case 6a - Last 1MB of big file
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
                 '%sload host 0:0 %x /%s %x 0x9c300000'
-                    % (fs_type, ADDR, BIG_FILE, LENGTH),
+                    % (fs_cmd_prefix, ADDR, BIG_FILE, LENGTH),
                 'printenv filesize'])
             assert('filesize=100000' in ''.join(output))
 
@@ -136,14 +136,14 @@
         """
         Test Case 7 - load, 1MB from the last 1MB in 2GB
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 7 - load (last 1MB in 2GB)'):
             # fails for ext as no offset support
             # Test Case 7a - One from the last 1MB chunk of 2GB
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
                 '%sload host 0:0 %x /%s %x 0x7ff00000'
-                    % (fs_type, ADDR, BIG_FILE, LENGTH),
+                    % (fs_cmd_prefix, ADDR, BIG_FILE, LENGTH),
                 'printenv filesize'])
             assert('filesize=100000' in ''.join(output))
 
@@ -157,14 +157,14 @@
         """
         Test Case 8 - load, reading first 1MB in 2GB
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 8 - load (first 1MB in 2GB)'):
             # fails for ext as no offset support
             # Test Case 8a - One from the start 1MB chunk from 2GB
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
                 '%sload host 0:0 %x /%s %x 0x80000000'
-                    % (fs_type, ADDR, BIG_FILE, LENGTH),
+                    % (fs_cmd_prefix, ADDR, BIG_FILE, LENGTH),
                 'printenv filesize'])
             assert('filesize=100000' in ''.join(output))
 
@@ -178,14 +178,14 @@
         """
         Test Case 9 - load, 1MB crossing 2GB boundary
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 9 - load (crossing 2GB boundary)'):
             # fails for ext as no offset support
             # Test Case 9a - One 1MB chunk crossing the 2GB boundary
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
                 '%sload host 0:0 %x /%s %x 0x7ff80000'
-                    % (fs_type, ADDR, BIG_FILE, LENGTH),
+                    % (fs_cmd_prefix, ADDR, BIG_FILE, LENGTH),
                 'printenv filesize'])
             assert('filesize=100000' in ''.join(output))
 
@@ -199,14 +199,14 @@
         """
         Test Case 10 - load, reading beyond file end'):
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 10 - load (beyond file end)'):
             # Generic failure case
             # Test Case 10 - 2MB chunk from the last 1MB of big file
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
                 '%sload host 0:0 %x /%s 0x00200000 0x9c300000'
-                    % (fs_type, ADDR, BIG_FILE),
+                    % (fs_cmd_prefix, ADDR, BIG_FILE),
                 'printenv filesize',
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
@@ -216,22 +216,22 @@
         """
         Test Case 11 - write'
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 11 - write'):
             # Read 1MB from small file
             # Write it back to test the writes
             # Test Case 11a - Check that the write succeeded
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, SMALL_FILE),
-                '%swrite host 0:0 %x /%s.w $filesize'
-                    % (fs_type, ADDR, SMALL_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, SMALL_FILE),
+                '%s%s host 0:0 %x /%s.w $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, SMALL_FILE)])
             assert('1048576 bytes written' in ''.join(output))
 
             # Test Case 11b - Check md5 of written to is same
             # as the one read from
             output = ubman.run_command_list([
-                '%sload host 0:0 %x /%s.w' % (fs_type, ADDR, SMALL_FILE),
+                '%sload host 0:0 %x /%s.w' % (fs_cmd_prefix, ADDR, SMALL_FILE),
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
             assert(md5val[0] in ''.join(output))
@@ -241,7 +241,7 @@
         """
         Test Case 12 - write to "." directory
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 12 - write (".")'):
             # Next test case checks writing a file whose dirent
             # is the first in the block, which is always true for "."
@@ -249,7 +249,8 @@
             # Test Case 12 - Check directory traversal
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%swrite host 0:0 %x /. 0x10' % (fs_type, ADDR)])
+                '%s%s host 0:0 %x /. 0x10'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR)])
             assert('Unable to write' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -257,23 +258,23 @@
         """
         Test Case 13 - write to a file with "/./<filename>"
         """
-        fs_type,fs_img,md5val = fs_obj_basic
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_basic
         with ubman.log.section('Test Case 13 - write  ("./<file>")'):
             # Read 1MB from small file
             # Write it via "same directory", i.e. "." dirent
             # Test Case 13a - Check directory traversal
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, SMALL_FILE),
-                '%swrite host 0:0 %x /./%s2 $filesize'
-                    % (fs_type, ADDR, SMALL_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, SMALL_FILE),
+                '%s%s host 0:0 %x /./%s2 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, SMALL_FILE)])
             assert('1048576 bytes written' in ''.join(output))
 
             # Test Case 13b - Check md5 of written to is same
             # as the one read from
             output = ubman.run_command_list([
                 'mw.b %x 00 100' % ADDR,
-                '%sload host 0:0 %x /./%s2' % (fs_type, ADDR, SMALL_FILE),
+                '%sload host 0:0 %x /./%s2' % (fs_cmd_prefix, ADDR, SMALL_FILE),
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
             assert(md5val[0] in ''.join(output))
@@ -282,7 +283,7 @@
             # as the one read from
             output = ubman.run_command_list([
                 'mw.b %x 00 100' % ADDR,
-                '%sload host 0:0 %x /%s2' % (fs_type, ADDR, SMALL_FILE),
+                '%sload host 0:0 %x /%s2' % (fs_cmd_prefix, ADDR, SMALL_FILE),
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
             assert(md5val[0] in ''.join(output))
diff --git a/test/py/tests/test_fs/test_ext.py b/test/py/tests/test_fs/test_ext.py
index 9c213f2..a75cd74 100644
--- a/test/py/tests/test_fs/test_ext.py
+++ b/test/py/tests/test_fs/test_ext.py
@@ -33,20 +33,20 @@
         """
         Test Case 1 - write a file with absolute path
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 1 - write with abs path'):
             # Test Case 1a - Check if command successfully returned
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x /dir1/%s.w1 $filesize'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x /dir1/%s.w1 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             assert('20480 bytes written' in ''.join(output))
 
             # Test Case 1b - Check md5 of file content
             output = ubman.run_command_list([
                 'mw.b %x 00 100' % ADDR,
-                '%sload host 0:0 %x /dir1/%s.w1' % (fs_type, ADDR, MIN_FILE),
+                '%sload host 0:0 %x /dir1/%s.w1' % (fs_cmd_prefix, ADDR, MIN_FILE),
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
             assert(md5val[0] in ''.join(output))
@@ -56,20 +56,20 @@
         """
         Test Case 2 - write to a file with relative path
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 2 - write with rel path'):
             # Test Case 2a - Check if command successfully returned
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x dir1/%s.w2 $filesize'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x dir1/%s.w2 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             assert('20480 bytes written' in ''.join(output))
 
             # Test Case 2b - Check md5 of file content
             output = ubman.run_command_list([
                 'mw.b %x 00 100' % ADDR,
-                '%sload host 0:0 %x dir1/%s.w2' % (fs_type, ADDR, MIN_FILE),
+                '%sload host 0:0 %x dir1/%s.w2' % (fs_cmd_prefix, ADDR, MIN_FILE),
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
             assert(md5val[0] in ''.join(output))
@@ -79,14 +79,14 @@
         """
         Test Case 3 - write to a file with invalid path
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 3 - write with invalid path'):
             # Test Case 3 - Check if command expectedly failed
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x /dir1/none/%s.w3 $filesize'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x /dir1/none/%s.w3 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             assert('Unable to write file /dir1/none/' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -94,22 +94,22 @@
         """
         Test Case 4 - write at non-zero offset, enlarging file size
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 4 - write at non-zero offset, enlarging file size'):
             # Test Case 4a - Check if command successfully returned
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x /dir1/%s.w4 $filesize'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x /dir1/%s.w4 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             output = ubman.run_command(
-                '%swrite host 0:0 %x /dir1/%s.w4 $filesize 0x1400'
-                    % (fs_type, ADDR, MIN_FILE))
+                '%s%s host 0:0 %x /dir1/%s.w4 $filesize 0x1400'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE))
             assert('20480 bytes written' in output)
 
             # Test Case 4b - Check size of written file
             output = ubman.run_command_list([
-                '%ssize host 0:0 /dir1/%s.w4' % (fs_type, MIN_FILE),
+                '%ssize host 0:0 /dir1/%s.w4' % (fs_cmd_prefix, MIN_FILE),
                 'printenv filesize',
                 'setenv filesize'])
             assert('filesize=6400' in ''.join(output))
@@ -117,7 +117,7 @@
             # Test Case 4c - Check md5 of file content
             output = ubman.run_command_list([
                 'mw.b %x 00 100' % ADDR,
-                '%sload host 0:0 %x /dir1/%s.w4' % (fs_type, ADDR, MIN_FILE),
+                '%sload host 0:0 %x /dir1/%s.w4' % (fs_cmd_prefix, ADDR, MIN_FILE),
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
             assert(md5val[1] in ''.join(output))
@@ -127,22 +127,22 @@
         """
         Test Case 5 - write at non-zero offset, shrinking file size
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 5 - write at non-zero offset, shrinking file size'):
             # Test Case 5a - Check if command successfully returned
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x /dir1/%s.w5 $filesize'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x /dir1/%s.w5 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             output = ubman.run_command(
-                '%swrite host 0:0 %x /dir1/%s.w5 0x1400 0x1400'
-                    % (fs_type, ADDR, MIN_FILE))
+                '%s%s host 0:0 %x /dir1/%s.w5 0x1400 0x1400'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE))
             assert('5120 bytes written' in output)
 
             # Test Case 5b - Check size of written file
             output = ubman.run_command_list([
-                '%ssize host 0:0 /dir1/%s.w5' % (fs_type, MIN_FILE),
+                '%ssize host 0:0 /dir1/%s.w5' % (fs_cmd_prefix, MIN_FILE),
                 'printenv filesize',
                 'setenv filesize'])
             assert('filesize=2800' in ''.join(output))
@@ -150,7 +150,7 @@
             # Test Case 5c - Check md5 of file content
             output = ubman.run_command_list([
                 'mw.b %x 00 100' % ADDR,
-                '%sload host 0:0 %x /dir1/%s.w5' % (fs_type, ADDR, MIN_FILE),
+                '%sload host 0:0 %x /dir1/%s.w5' % (fs_cmd_prefix, ADDR, MIN_FILE),
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
             assert(md5val[2] in ''.join(output))
@@ -160,22 +160,22 @@
         """
         Test Case 6 - write nothing at the start, truncating to zero
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 6 - write nothing at the start, truncating to zero'):
             # Test Case 6a - Check if command successfully returned
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x /dir1/%s.w6 $filesize'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x /dir1/%s.w6 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             output = ubman.run_command(
-                '%swrite host 0:0 %x /dir1/%s.w6 0 0'
-                    % (fs_type, ADDR, MIN_FILE))
+                '%s%s host 0:0 %x /dir1/%s.w6 0 0'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE))
             assert('0 bytes written' in output)
 
             # Test Case 6b - Check size of written file
             output = ubman.run_command_list([
-                '%ssize host 0:0 /dir1/%s.w6' % (fs_type, MIN_FILE),
+                '%ssize host 0:0 /dir1/%s.w6' % (fs_cmd_prefix, MIN_FILE),
                 'printenv filesize',
                 'setenv filesize'])
             assert('filesize=0' in ''.join(output))
@@ -185,22 +185,22 @@
         """
         Test Case 7 - write at the end (append)
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 7 - write at the end (append)'):
             # Test Case 7a - Check if command successfully returned
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x /dir1/%s.w7 $filesize'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x /dir1/%s.w7 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             output = ubman.run_command(
-                '%swrite host 0:0 %x /dir1/%s.w7 $filesize $filesize'
-                    % (fs_type, ADDR, MIN_FILE))
+                '%s%s host 0:0 %x /dir1/%s.w7 $filesize $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE))
             assert('20480 bytes written' in output)
 
             # Test Case 7b - Check size of written file
             output = ubman.run_command_list([
-                '%ssize host 0:0 /dir1/%s.w7' % (fs_type, MIN_FILE),
+                '%ssize host 0:0 /dir1/%s.w7' % (fs_cmd_prefix, MIN_FILE),
                 'printenv filesize',
                 'setenv filesize'])
             assert('filesize=a000' in ''.join(output))
@@ -208,7 +208,7 @@
             # Test Case 7c - Check md5 of file content
             output = ubman.run_command_list([
                 'mw.b %x 00 100' % ADDR,
-                '%sload host 0:0 %x /dir1/%s.w7' % (fs_type, ADDR, MIN_FILE),
+                '%sload host 0:0 %x /dir1/%s.w7' % (fs_cmd_prefix, ADDR, MIN_FILE),
                 'md5sum %x $filesize' % ADDR,
                 'setenv filesize'])
             assert(md5val[3] in ''.join(output))
@@ -218,17 +218,17 @@
         """
         Test Case 8 - write at offset beyond the end of file
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 8 - write beyond the end'):
             # Test Case 8a - Check if command expectedly failed
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x /dir1/%s.w8 $filesize'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x /dir1/%s.w8 $filesize'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             output = ubman.run_command(
-                '%swrite host 0:0 %x /dir1/%s.w8 0x1400 %x'
-                    % (fs_type, ADDR, MIN_FILE, 0x100000 + 0x1400))
+                '%s%s host 0:0 %x /dir1/%s.w8 0x1400 %x'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE, 0x100000 + 0x1400))
             assert('Unable to write file /dir1' in output)
             assert_fs_integrity(fs_type, fs_img)
 
@@ -236,14 +236,14 @@
         """
         Test Case 9 - write to a non-existing file at non-zero offset
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 9 - write to non-existing file with non-zero offset'):
             # Test Case 9a - Check if command expectedly failed
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%sload host 0:0 %x /%s' % (fs_type, ADDR, MIN_FILE),
-                '%swrite host 0:0 %x /dir1/%s.w9 0x1400 0x1400'
-                    % (fs_type, ADDR, MIN_FILE)])
+                '%sload host 0:0 %x /%s' % (fs_cmd_prefix, ADDR, MIN_FILE),
+                '%s%s host 0:0 %x /dir1/%s.w9 0x1400 0x1400'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MIN_FILE)])
             assert('Unable to write file /dir1' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -252,7 +252,7 @@
         'Test Case 10 - create/delete as many directories under root directory
         as amount of directory entries goes beyond one cluster size)'
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 10 - create/delete (many)'):
             # Test Case 10a - Create many files
             #   Please note that the size of directory entry is 32 bytes.
@@ -262,9 +262,9 @@
 
             for i in range(0, 66):
                 output = ubman.run_command(
-                    '%swrite host 0:0 %x /FILE0123456789_%02x 100'
-                    % (fs_type, ADDR, i))
-            output = ubman.run_command('%sls host 0:0 /' % fs_type)
+                    '%s%s host 0:0 %x /FILE0123456789_%02x 100'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, i))
+            output = ubman.run_command('%sls host 0:0 /' % fs_cmd_prefix)
             assert('FILE0123456789_00' in output)
             assert('FILE0123456789_41' in output)
 
@@ -272,8 +272,8 @@
             for i in range(0, 66):
                 output = ubman.run_command(
                     '%srm host 0:0 /FILE0123456789_%02x'
-                    % (fs_type, i))
-            output = ubman.run_command('%sls host 0:0 /' % fs_type)
+                    % (fs_cmd_prefix, i))
+            output = ubman.run_command('%sls host 0:0 /' % fs_cmd_prefix)
             assert(not 'FILE0123456789_00' in output)
             assert(not 'FILE0123456789_41' in output)
 
@@ -281,9 +281,9 @@
             # Please note no.64 and 65 are intentionally re-created
             for i in range(64, 128):
                 output = ubman.run_command(
-                    '%swrite host 0:0 %x /FILE0123456789_%02x 100'
-                    % (fs_type, ADDR, i))
-            output = ubman.run_command('%sls host 0:0 /' % fs_type)
+                    '%s%s host 0:0 %x /FILE0123456789_%02x 100'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, i))
+            output = ubman.run_command('%sls host 0:0 /' % fs_cmd_prefix)
             assert('FILE0123456789_40' in output)
             assert('FILE0123456789_79' in output)
 
@@ -294,7 +294,7 @@
         'Test Case 11 - create/delete as many directories under non-root
         directory as amount of directory entries goes beyond one cluster size)'
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 11 - create/delete (many)'):
             # Test Case 11a - Create many files
             #   Please note that the size of directory entry is 32 bytes.
@@ -304,9 +304,9 @@
 
             for i in range(0, 66):
                 output = ubman.run_command(
-                    '%swrite host 0:0 %x /dir1/FILE0123456789_%02x 100'
-                    % (fs_type, ADDR, i))
-            output = ubman.run_command('%sls host 0:0 /dir1' % fs_type)
+                    '%s%s host 0:0 %x /dir1/FILE0123456789_%02x 100'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, i))
+            output = ubman.run_command('%sls host 0:0 /dir1' % fs_cmd_prefix)
             assert('FILE0123456789_00' in output)
             assert('FILE0123456789_41' in output)
 
@@ -314,8 +314,8 @@
             for i in range(0, 66):
                 output = ubman.run_command(
                     '%srm host 0:0 /dir1/FILE0123456789_%02x'
-                    % (fs_type, i))
-            output = ubman.run_command('%sls host 0:0 /dir1' % fs_type)
+                    % (fs_cmd_prefix, i))
+            output = ubman.run_command('%sls host 0:0 /dir1' % fs_cmd_prefix)
             assert(not 'FILE0123456789_00' in output)
             assert(not 'FILE0123456789_41' in output)
 
@@ -323,9 +323,9 @@
             # Please note no.64 and 65 are intentionally re-created
             for i in range(64, 128):
                 output = ubman.run_command(
-                    '%swrite host 0:0 %x /dir1/FILE0123456789_%02x 100'
-                    % (fs_type, ADDR, i))
-            output = ubman.run_command('%sls host 0:0 /dir1' % fs_type)
+                    '%s%s host 0:0 %x /dir1/FILE0123456789_%02x 100'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, i))
+            output = ubman.run_command('%sls host 0:0 /dir1' % fs_cmd_prefix)
             assert('FILE0123456789_40' in output)
             assert('FILE0123456789_79' in output)
 
@@ -335,15 +335,15 @@
         """
         Test Case 12 - write plain and mangle file
         """
-        fs_type,fs_img,md5val = fs_obj_ext
+        fs_type,fs_cmd_prefix,fs_cmd_write,fs_img,md5val = fs_obj_ext
         with ubman.log.section('Test Case 12 - write plain and mangle file'):
             # Test Case 12a - Check if command successfully returned
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%swrite host 0:0 %x /%s 0'
-                    % (fs_type, ADDR, PLAIN_FILE),
-                '%swrite host 0:0 %x /%s 0'
-                    % (fs_type, ADDR, MANGLE_FILE)])
+                '%s%s host 0:0 %x /%s 0'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, PLAIN_FILE),
+                '%s%s host 0:0 %x /%s 0'
+                    % (fs_cmd_prefix, fs_cmd_write, ADDR, MANGLE_FILE)])
             assert('0 bytes written' in ''.join(output))
             # Test Case 12b - Read file system content
             output = check_output('mdir -i %s' % fs_img, shell=True).decode()
diff --git a/test/py/tests/test_fs/test_mkdir.py b/test/py/tests/test_fs/test_mkdir.py
index df680a8..1578c3c 100644
--- a/test/py/tests/test_fs/test_mkdir.py
+++ b/test/py/tests/test_fs/test_mkdir.py
@@ -18,16 +18,16 @@
         """
         Test Case 1 - create a directory under a root
         """
-        fs_type,fs_img = fs_obj_mkdir
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_mkdir
         with ubman.log.section('Test Case 1 - mkdir'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%smkdir host 0:0 dir1' % fs_type,
-                '%sls host 0:0 /' % fs_type])
+                '%smkdir host 0:0 dir1' % fs_cmd_prefix,
+                '%sls host 0:0 /' % fs_cmd_prefix])
             assert('dir1/' in ''.join(output))
 
             output = ubman.run_command(
-                '%sls host 0:0 dir1' % fs_type)
+                '%sls host 0:0 dir1' % fs_cmd_prefix)
             assert('./'   in output)
             assert('../'  in output)
             assert_fs_integrity(fs_type, fs_img)
@@ -37,16 +37,16 @@
         """
         Test Case 2 - create a directory under a sub-directory
         """
-        fs_type,fs_img = fs_obj_mkdir
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_mkdir
         with ubman.log.section('Test Case 2 - mkdir (sub-sub directory)'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%smkdir host 0:0 dir1/dir2' % fs_type,
-                '%sls host 0:0 dir1' % fs_type])
+                '%smkdir host 0:0 dir1/dir2' % fs_cmd_prefix,
+                '%sls host 0:0 dir1' % fs_cmd_prefix])
             assert('dir2/' in ''.join(output))
 
             output = ubman.run_command(
-                '%sls host 0:0 dir1/dir2' % fs_type)
+                '%sls host 0:0 dir1/dir2' % fs_cmd_prefix)
             assert('./'   in output)
             assert('../'  in output)
             assert_fs_integrity(fs_type, fs_img)
@@ -56,11 +56,11 @@
         Test Case 3 - trying to create a directory with a non-existing
         path should fail
         """
-        fs_type,fs_img = fs_obj_mkdir
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_mkdir
         with ubman.log.section('Test Case 3 - mkdir (non-existing path)'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%smkdir host 0:0 none/dir3' % fs_type])
+                '%smkdir host 0:0 none/dir3' % fs_cmd_prefix])
             assert('Unable to create a directory' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -68,11 +68,11 @@
         """
         Test Case 4 - trying to create "." should fail
         """
-        fs_type,fs_img = fs_obj_mkdir
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_mkdir
         with ubman.log.section('Test Case 4 - mkdir (".")'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%smkdir host 0:0 .' % fs_type])
+                '%smkdir host 0:0 .' % fs_cmd_prefix])
             assert('Unable to create a directory' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -80,11 +80,11 @@
         """
         Test Case 5 - trying to create ".." should fail
         """
-        fs_type,fs_img = fs_obj_mkdir
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_mkdir
         with ubman.log.section('Test Case 5 - mkdir ("..")'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%smkdir host 0:0 ..' % fs_type])
+                '%smkdir host 0:0 ..' % fs_cmd_prefix])
             assert('Unable to create a directory' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -93,29 +93,29 @@
         'Test Case 6 - create as many directories as amount of directory
         entries goes beyond a cluster size)'
         """
-        fs_type,fs_img = fs_obj_mkdir
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_mkdir
         with ubman.log.section('Test Case 6 - mkdir (create many)'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%smkdir host 0:0 dir6' % fs_type,
-                '%sls host 0:0 /' % fs_type])
+                '%smkdir host 0:0 dir6' % fs_cmd_prefix,
+                '%sls host 0:0 /' % fs_cmd_prefix])
             assert('dir6/' in ''.join(output))
 
             for i in range(0, 20):
                 output = ubman.run_command(
                     '%smkdir host 0:0 dir6/0123456789abcdef%02x'
-                    % (fs_type, i))
-            output = ubman.run_command('%sls host 0:0 dir6' % fs_type)
+                    % (fs_cmd_prefix, i))
+            output = ubman.run_command('%sls host 0:0 dir6' % fs_cmd_prefix)
             assert('0123456789abcdef00/'  in output)
             assert('0123456789abcdef13/'  in output)
 
             output = ubman.run_command(
-                '%sls host 0:0 dir6/0123456789abcdef13/.' % fs_type)
+                '%sls host 0:0 dir6/0123456789abcdef13/.' % fs_cmd_prefix)
             assert('./'   in output)
             assert('../'  in output)
 
             output = ubman.run_command(
-                '%sls host 0:0 dir6/0123456789abcdef13/..' % fs_type)
+                '%sls host 0:0 dir6/0123456789abcdef13/..' % fs_cmd_prefix)
             assert('0123456789abcdef00/'  in output)
             assert('0123456789abcdef13/'  in output)
             assert_fs_integrity(fs_type, fs_img)
diff --git a/test/py/tests/test_fs/test_unlink.py b/test/py/tests/test_fs/test_unlink.py
index 7e911f0..1e2df3d 100644
--- a/test/py/tests/test_fs/test_unlink.py
+++ b/test/py/tests/test_fs/test_unlink.py
@@ -19,16 +19,16 @@
         """
         Test Case 1 - delete a file
         """
-        fs_type,fs_img = fs_obj_unlink
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_unlink
         with ubman.log.section('Test Case 1 - unlink (file)'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%srm host 0:0 dir1/file1' % fs_type,
-                '%sls host 0:0 dir1/file1' % fs_type])
+                '%srm host 0:0 dir1/file1' % fs_cmd_prefix,
+                '%sls host 0:0 dir1/file1' % fs_cmd_prefix])
             assert('' == ''.join(output))
 
             output = ubman.run_command(
-                '%sls host 0:0 dir1/' % fs_type)
+                '%sls host 0:0 dir1/' % fs_cmd_prefix)
             assert(not 'file1' in output)
             assert('file2' in output)
             assert_fs_integrity(fs_type, fs_img)
@@ -37,18 +37,18 @@
         """
         Test Case 2 - delete many files
         """
-        fs_type,fs_img = fs_obj_unlink
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_unlink
         with ubman.log.section('Test Case 2 - unlink (many)'):
             output = ubman.run_command('host bind 0 %s' % fs_img)
 
             for i in range(0, 20):
                 output = ubman.run_command_list([
-                    '%srm host 0:0 dir2/0123456789abcdef%02x' % (fs_type, i),
-                    '%sls host 0:0 dir2/0123456789abcdef%02x' % (fs_type, i)])
+                    '%srm host 0:0 dir2/0123456789abcdef%02x' % (fs_cmd_prefix, i),
+                    '%sls host 0:0 dir2/0123456789abcdef%02x' % (fs_cmd_prefix, i)])
                 assert('' == ''.join(output))
 
             output = ubman.run_command(
-                '%sls host 0:0 dir2' % fs_type)
+                '%sls host 0:0 dir2' % fs_cmd_prefix)
             assert('0 file(s), 2 dir(s)' in output)
             assert_fs_integrity(fs_type, fs_img)
 
@@ -56,11 +56,11 @@
         """
         Test Case 3 - trying to delete a non-existing file should fail
         """
-        fs_type,fs_img = fs_obj_unlink
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_unlink
         with ubman.log.section('Test Case 3 - unlink (non-existing)'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%srm host 0:0 dir1/nofile' % fs_type])
+                '%srm host 0:0 dir1/nofile' % fs_cmd_prefix])
             assert('nofile: doesn\'t exist' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -68,15 +68,15 @@
         """
         Test Case 4 - delete an empty directory
         """
-        fs_type,fs_img = fs_obj_unlink
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_unlink
         with ubman.log.section('Test Case 4 - unlink (directory)'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%srm host 0:0 dir4' % fs_type])
+                '%srm host 0:0 dir4' % fs_cmd_prefix])
             assert('' == ''.join(output))
 
             output = ubman.run_command(
-                '%sls host 0:0 /' % fs_type)
+                '%sls host 0:0 /' % fs_cmd_prefix)
             assert(not 'dir4' in output)
             assert_fs_integrity(fs_type, fs_img)
 
@@ -85,11 +85,11 @@
         Test Case 5 - trying to deleting a non-empty directory ".."
         should fail
         """
-        fs_type,fs_img = fs_obj_unlink
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_unlink
         with ubman.log.section('Test Case 5 - unlink ("non-empty directory")'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%srm host 0:0 dir5' % fs_type])
+                '%srm host 0:0 dir5' % fs_cmd_prefix])
             assert('directory is not empty' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -97,11 +97,11 @@
         """
         Test Case 6 - trying to deleting a "." should fail
         """
-        fs_type,fs_img = fs_obj_unlink
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_unlink
         with ubman.log.section('Test Case 6 - unlink (".")'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%srm host 0:0 dir5/.' % fs_type])
+                '%srm host 0:0 dir5/.' % fs_cmd_prefix])
             assert('directory is not empty' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)
 
@@ -109,10 +109,10 @@
         """
         Test Case 7 - trying to deleting a ".." should fail
         """
-        fs_type,fs_img = fs_obj_unlink
+        fs_type,fs_cmd_prefix,fs_img = fs_obj_unlink
         with ubman.log.section('Test Case 7 - unlink ("..")'):
             output = ubman.run_command_list([
                 'host bind 0 %s' % fs_img,
-                '%srm host 0:0 dir5/..' % fs_type])
+                '%srm host 0:0 dir5/..' % fs_cmd_prefix])
             assert('directory is not empty' in ''.join(output))
             assert_fs_integrity(fs_type, fs_img)