diff --git a/releng/auto_isocontent b/releng/auto_isocontent
index e24a8fab..1141f1c8 100755
--- a/releng/auto_isocontent
+++ b/releng/auto_isocontent
@@ -6,6 +6,8 @@
 
 # Test the correct handling of hardlinks by xorriso options
 # -update_r , -hardlinks perform_update , and -extract
+# If there is support for ACLs or xattr in xorriso and on the local system,
+# then test recording and restoring of these features.
 
 not_in_releng_exit() {
   printf "\nPlease execute the tests from releng directory.\n\n"
@@ -67,6 +69,7 @@ then
   exit 3
 fi
 
+
 # All must be set at this point
 printf "\n${SELF}: Setting up $on_disk with several hardlinks\n" >&2
 echo test_content >"$on_disk"/file_1 || exit 1
@@ -74,7 +77,6 @@ echo test_content >"$on_disk"/file_2 || exit 1
 ln "$on_disk"/file_1 "$on_disk"/file_1_link_a || exit 1
 ln "$on_disk"/file_1 "$on_disk"/file_1_link_b || exit 1
 ln "$on_disk"/file_2 "$on_disk"/file_2_link_a || exit 1
-ls -l "$on_disk"/*
 
 # trivial ISO 9660 image validation routine
 is_valid_iso9660() {
@@ -92,6 +94,73 @@ is_valid_iso9660() {
  fi
 }
 
+# Create test file and find out whether ACLs and/or xattr are available.
+# Users known on GNU/Linux and FreeBSD: root games daemon man
+# Groups                              : daemon games bin sshd sys
+acl_xattr_test_file="$on_disk"/acl_xattr_test_file
+echo echo hello world >"$acl_xattr_test_file" || exit 1
+sys=$(uname -s)
+acls=no
+if ( setfacl -m u::rwx,u:root:rwx,g:sys:rwx,u:daemon:r,mask::rwx \
+             "$acl_xattr_test_file" ) >/dev/null 2>&1
+then
+  if ( getfacl "$acl_xattr_test_file" ) >/dev/null 2>&1
+  then
+    acls=yes
+  fi
+fi
+xattrs=no
+extattrs=no
+if ( setfattr -n user.test_xattr -v test_value "$acl_xattr_test_file" ) \
+   >/dev/null 2>&1
+then
+  if ( getfattr "$acl_xattr_test_file" ) >/dev/null 2>&1
+  then
+    xattrs=yes
+    setfattr -n user.long_data -v 0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789 "$acl_xattr_test_file"
+    setfattr -n user.more_data -v 01234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789 "$acl_xattr_test_file"
+  fi
+fi
+if test "$xattrs" = no
+then
+
+  # >>> Try FreeBSD style setextattr
+  dummy=dummy
+
+fi
+
+echo
+echo "${SELF}: Detected sys='$sys' , acls=$acls , xattrs=$xattrs , extattrs=$extattrs"
+
+# Examine capabilities of xorriso 
+xorriso_acls=no
+xorriso_xattrs=no
+extras=$("$xorriso" -list_extras all 2>/dev/null)
+if test "$?" = 0
+then
+  if echo "$extras" | fgrep 'Local ACL    : yes' >/dev/null 2>&1
+  then
+    xorriso_acls=yes
+  fi
+  if echo "$extras" | fgrep 'Local xattr  : yes' >/dev/null 2>&1
+  then
+    xorriso_xattrs=yes
+  fi
+fi
+if test "$xorriso_acls" = no
+then
+  acls=no
+fi
+if test "$xorriso_xattrs" = no
+then
+  xattrs=no
+fi
+  
+echo "${SELF}: Detected xorriso_acls=$xorriso_acls , xorriso_xattrs=$xorriso_xattrs"
+echo
+ls -l "$on_disk"/*
+
+
 echo -e "\n${SELF}: Producing simple image via -o" >&2
 "$xorriso" -as mkisofs "$on_disk" -o      "$workdir"/image_minus_o.iso
 is_valid_iso9660                          "$workdir"/image_minus_o.iso
@@ -115,9 +184,8 @@ echo -e "\n${SELF}: Producing simple image with for_backup/update_r/hardlinks" >
 ret=$?
 if test "$ret" -gt 0 -a "$ret" -lt 32
 then
-  printf "\n${SELF}: xorriso write run failed\n\n" >&2
+  printf "\nFAIL : ${SELF} : xorriso write run failed\n\n"
   cleanup
-  printf "${SELF}: FAILED\n"
   exit 1
 fi
 is_valid_iso9660                         "$image_file"
@@ -141,7 +209,7 @@ then
   failure=1
   echo >&2
   echo "$msg" >&2
-  printf "\nFAIL : ${SELF} : -assert_volid test not properly performed\n\n" >&2
+  printf "\nFAIL : ${SELF} : -assert_volid test not properly performed\n\n"
 else
   failure=1
   printf "\nFAIL : ${SELF} : -assert_volid did not snap\n\n" >&2
@@ -159,9 +227,8 @@ echo -e "\n${SELF}: Copying from image to temporary disk tree" >&2
 ret=$?
 if test "$ret" -gt 0 -a "$ret" -lt 32
 then
-  printf "\n${SELF}: xorriso file extraction run failed\n\n" >&2
+  printf "\nFAIL : ${SELF} : xorriso file extraction run failed\n\n"
   cleanup
-  printf "${SELF}: FAILED\n"
   exit 1
 fi
 
@@ -187,10 +254,10 @@ fi
 printf "\n${SELF}: Checking for hardlinks being siblings...\n"
 ls -l "$copy_on_disk"/*
 x=$(echo $(ls -l "$copy_on_disk"/* | awk '{print $2}'))
-expected="3 3 3 2 2"
+expected="1 3 3 3 2 2"
 if test x"$x" = x"$expected"
 then
-  printf "\n${SELF}: Checking for hardlinks being siblings. Done. OK.\n" >&2
+  printf "${SELF}: Checking for hardlinks being siblings done: ok.\n" >&2
 else
   printf "\nFAIL : ${SELF} : Link count of extracted files is not as expected." >&2
   printf "\n${SELF}: Expected:  $expected" >&2
@@ -198,7 +265,50 @@ else
   failure=1
 fi
 
+if test "$acls" = yes
+then
+  printf "\n${SELF}: Checking ACLs ...\n" >&2
+  acl_on_disk=$(getfacl "$acl_xattr_test_file" | grep -v '^# file:' | sort)
+  acl_in_copy=$(getfacl "$copy_on_disk"/acl_xattr_test_file | 
+                grep -v '^# file:' | sort)
+  if test "$acl_on_disk" = "$acl_in_copy"
+  then
+    printf "${SELF}: Checking ACLs done: ok.\n" >&2
+  else
+    printf "\nFAIL : ${SELF} : ACL mismatch between original and extracted copy\n"
+    printf "\nOriginal:\n${acl_on_disk}\n"
+    printf "\nCopy:\n${acl_in_copy}\n"
+    failure=1
+  fi
+fi
+
+if test "$xattrs" = yes
+then
+  printf "\n${SELF}: Checking xattr via getfattr ...\n" >&2
+  xattr_on_disk=$(getfattr "$acl_xattr_test_file" | \
+                  grep -v '^# file:' | grep -v '^$' | \sort)
+  xattr_in_copy=$(getfattr "$copy_on_disk"/acl_xattr_test_file | 
+                  grep -v '^# file:' | grep -v '^$' | sort)
+  if test "$xattr_on_disk" = "$xattr_in_copy"
+  then
+    num_xattr=$(echo "$xattr_on_disk" | wc -l)
+    printf "${SELF}: Checking xattr done: $num_xattr attributes, ok.\n" >&2
+  else
+    printf "\nFAIL : ${SELF} : xattr mismatch between original and extracted copy\n"
+    printf "\nOriginal:\n${xattr_on_disk}\n"
+    printf "\nCopy:\n${xattr_in_copy}\n"
+    failure=1
+  fi
+elif test "$extattr" = yes
+then
+
+  # >>> Compare xattr of "$acl_xattr_test_file" by getextattr
+  dummy=dummy
+
+fi
+
 #
+echo
 cleanup
 
 # Report result