diff --git a/btrbk b/btrbk
index 5cff413..aae1a25 100755
--- a/btrbk
+++ b/btrbk
@@ -232,6 +232,7 @@ my %backend_cmd_map = (
                            "btrfs receive"            => [ "sudo", "-n", "btrfs", "receive"               ],
                            "btrfs filesystem usage"   => [ "sudo", "-n", "btrfs", "filesystem", "usage"   ],
                            "btrfs qgroup destroy"     => [ "sudo", "-n", "btrfs", "qgroup", "destroy"     ],
+                           "readlink"                 => [ "sudo", "-n", "readlink"                       ],
                          },
 );
 
@@ -1813,7 +1814,7 @@ sub system_realpath($)
 
   my $path = $vol->{PATH} // die;;
   my @quiet = ($loglevel < 3) ? ('-q') : ();
-  my $ret = run_cmd(cmd => [ qw(readlink), '-e', @quiet, { unsafe => $path } ],
+  my $ret = run_cmd(cmd => vinfo_cmd($vol, "readlink", '-e', @quiet, { unsafe => $path } ),
                     rsh => vinfo_rsh($vol),
                     non_destructive => 1,
                    );
@@ -2429,7 +2430,6 @@ sub vinfo_cmd($$@)
   }
   else {
     my @ret_cmd = split(/\s/, $cmd);
-    die unless($ret_cmd[0] eq 'btrfs');
     TRACE "vinfo_cmd: no mapping found for backend=$backend cmd=\"$cmd\", assuming btrfs-progs: " . join(' ', @ret_cmd);
     $ret = [ @ret_cmd, @cmd_args ];
   }
diff --git a/doc/btrbk.conf.5.asciidoc b/doc/btrbk.conf.5.asciidoc
index 4fed055..e817f52 100644
--- a/doc/btrbk.conf.5.asciidoc
+++ b/doc/btrbk.conf.5.asciidoc
@@ -345,8 +345,8 @@ btrfs-progs-btrbk::
 btrfs-progs-sudo::
     btrfs commands are prefixed with "sudo -n" (e.g. "sudo -n btrfs
     subvolume show" instead of "btrfs subvolume show"). Make sure to
-    have appropriate (root) permissions for "btrfs" command groups in
-    /etc/sudoers.
+    have appropriate (root) permissions for the "btrfs" command groups
+    and the "readlink" command in /etc/sudoers.
 --
 +
 For convenience, it is also possible to set *backend_local* or
diff --git a/ssh_filter_btrbk.sh b/ssh_filter_btrbk.sh
index 69775c1..8f47c46 100755
--- a/ssh_filter_btrbk.sh
+++ b/ssh_filter_btrbk.sh
@@ -163,7 +163,7 @@ done
 
 allow_cmd "${sudo_prefix}btrfs subvolume show"; # subvolume queries are always allowed
 allow_exact_cmd "${sudo_prefix}btrfs subvolume list ${file_match}"; # subvolume queries are always allowed
-allow_cmd "readlink"                            # used to resolve mountpoints
+allow_cmd "${sudo_prefix}readlink"              # used to resolve mountpoints
 allow_exact_cmd "cat /proc/self/mountinfo"      # used to resolve mountpoints
 allow_exact_cmd "cat /proc/self/mounts"         # legacy, for btrbk < 0.27.0