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Add rd.kiwi.install.retain_last deployment option
Instructs an OEM installation to retain the contents of the last partition on the target disk. This setting is only useful if the last partition does not belong to the main OS e.g. an extra data partition added via the spare_part attribute in the type setup of the image description. The implementation also checks if the start address of the last partition on the target disk matches with the start adress of the image to be deployed. Only if they match the data on the last partition can be retained.
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‎doc/source/concept_and_workflow/customize_the_boot_process.rst‎

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Original file line numberDiff line numberDiff line change
@@ -222,6 +222,17 @@ the available kernel boot parameters for these modules:
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Note that options starting with `rd.kiwi` are not passed to avoid
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side effects.
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``rd.kiwi.install.retain_last``
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Instructs an OEM installation to retain the contents of the
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last partition on the target disk. This setting is only useful
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if the last partition does not belong to the main OS e.g. an
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extra data partition added via the `spare_part` attribute in
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the type setup of the image description. The implementation
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also checks if the start address of the last partition on the
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target disk matches with the start adress of the image to be
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deployed. Only if they match the data on the last partition
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can be retained.
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``rd.kiwi.oem.luks.reencrypt``
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For OEM LUKS2 encrypted disk images. If set, reencrypts the disk
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prior an eventual resize and therefore creates a new key pool and

‎dracut/modules.d/55kiwi-dump/kiwi-dump-image.sh‎

Lines changed: 185 additions & 9 deletions
Original file line numberDiff line numberDiff line change
@@ -330,15 +330,50 @@ function dump_image {
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local load_text="Loading ${image_basename}..."
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local title_text="Installation..."
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local dump
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local parttable
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local count_32k
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local image_size
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local count=0
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local block_size=32k
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# can we dump this
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check_image_fits_target "${image_target}"
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# select dump method
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if [ -n "${image_from_remote}" ];then
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dump=dump_remote_image
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else
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dump=dump_local_image
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fi
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340-
check_image_fits_target "${image_target}"
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# setup blocks and blocksize to retain last
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if getargbool 0 rd.kiwi.install.retain_last; then
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if [ -n "${image_from_remote}" ];then
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image_size=$((blocks * blocksize))
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parttable=$(
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fetch_remote_partition_table "${image_source}" "${image_size}"
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)
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else
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parttable=$(
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fetch_local_partition_table "${image_source}"
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)
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fi
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if compatible_to_retain "${parttable}" "${image_target}"; then
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count=$(get_disk_offset_retain_last_partition "${parttable}")
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fi
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if [ "${count}" -gt 0 ];then
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block_size=$(get_sector_size_from_table_dump "${parttable}")
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count_32k=$(
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optimize_count_for_32k_blocksize "${block_size}" "${count}"
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)
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if [ ! "${count}" = "${count_32k}" ];then
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count="${count_32k}"
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block_size=32k
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fi
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fi
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fi
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# last chance to stop us
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if [ "${kiwi_oemunattended}" = "false" ];then
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local ack_dump_text="Destroying ALL data on ${image_target}, continue ?"
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if ! run_dialog --yesno "\"${ack_dump_text}\"" 7 80; then
@@ -347,48 +382,182 @@ function dump_image {
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fi
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fi
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# deploy
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echo "${load_text} [${image_target}]..."
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if command -v pv &>/dev/null && [ "${kiwi_oemsilentinstall}" = "false" ]
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then
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# dump with dialog based progress information
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setup_progress_fifo ${progress}
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eval "${dump}" "${image_source}" "${image_target}" "${progress}" &
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eval \
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"${dump}" \
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"${image_source}" \
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"${image_target}" \
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"${count}" \
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"${block_size}" \
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"${progress}" \
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&
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run_progress_dialog "${load_text}" "${title_text}"
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else
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# dump with silently blocked console
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if ! eval "${dump}" "${image_source}" "${image_target}"; then
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if ! eval \
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"${dump}" \
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"${image_source}" \
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"${image_target}" \
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"${count}" \
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"${block_size}"
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then
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report_and_quit "Failed to install image"
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fi
362411
fi
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if [ "${count}" -gt 0 ]; then
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recreate_last_partition "${image_target}"
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fi
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}
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function fetch_local_partition_table {
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local image_source=$1
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local parttable=/tmp/parttable
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sfdisk -d "${image_source}" > "${parttable}" 2>/dev/null
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echo "${parttable}"
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}
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function fetch_remote_partition_table {
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local image_source=$1
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local image_size=$2
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local parttable=/tmp/parttable
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dd if=/dev/zero of=/tmp/table bs=1 count=0 seek="${image_size}" &>/dev/null
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fetch_file "${image_source}" 2>/dev/null | dd of=/tmp/table bs=512 count=1 conv=notrunc &>/dev/null
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sfdisk -d /tmp/table > "${parttable}" 2>/dev/null
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echo "${parttable}"
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}
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function get_sector_size_from_table_dump {
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local parttable=$1
436+
sector_size=$(grep sector-size: "${parttable}" | cut -f2 -d:)
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echo "${sector_size}"
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}
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function compatible_to_retain {
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local parttable=$1
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local image_target=$2
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local source_start
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local target_start
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source_start=$(
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tail -n 1 "${parttable}" | cut -f2 -d= | cut -f1 -d,
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)
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target_start=$(
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sfdisk -d "${image_target}" 2>/dev/null |\
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tail -n 1 | cut -f2 -d= | cut -f1 -d,
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)
452+
if [ -z "${source_start}" ] || [ -z "${target_start}" ];then
453+
# no partition information for either source or target
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# broken or net new deployment on empty disk
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touch /tmp/retain_not_applicable
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return 1
457+
fi
458+
if [ ! "${source_start}" = "${target_start}" ];then
459+
report_and_quit "Cannot retain partition, start address mismatch"
460+
fi
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return 0
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}
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function get_disk_offset_retain_last_partition {
465+
local parttable=$1
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local next_to_last
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local start
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local size
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local offset
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next_to_last=$(tail -n 2 "${parttable}" | head -n 1)
471+
if [ -n "${next_to_last}" ];then
472+
start=$(echo "${next_to_last}" | cut -f2 -d= | cut -f1 -d,)
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size=$(echo "${next_to_last}" | cut -f3 -d= | cut -f1 -d,)
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offset=$((start + size))
475+
echo "${offset}"
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else
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echo 0
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fi
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}
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function optimize_count_for_32k_blocksize {
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local block_size=$1
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local count=$2
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local dump_bytes
485+
dump_bytes=$((block_size * count))
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if [ $((${dump_bytes} % 32768)) -eq 0 ];then
487+
# dump_bytes is a multiple of 32k, use it for better I/O performance
488+
count=$((${dump_bytes} / 32768))
489+
fi
490+
echo "${count}"
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}
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493+
function recreate_last_partition {
494+
local image_target=$1
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local table_type
496+
table_type=$(get_partition_table_type "${image_target}")
497+
if [ "${table_type}" = "gpt" ];then
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relocate_gpt_at_end_of_disk "${image_target}"
499+
fi
500+
sfdisk -d "${image_target}" > /tmp/parttable 2>/dev/null
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head -n -1 /tmp/parttable > /tmp/parttable_1
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tail -n 1 /tmp/parttable > /tmp/parttable_2
503+
if [ "${table_type}" = "gpt" ];then
504+
sed -ie "s@\(/dev/.* : start=.*\), size=.*, \(type=.*, uuid=.*, name=\".*\"\)@\1, \2@" \
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/tmp/parttable_2
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else
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sed -ie "s@\(/dev/.* : start=.*\), size=.*, \(type=.*\)@\1, \2@" \
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/tmp/parttable_2
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fi
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cat /tmp/parttable_1 /tmp/parttable_2 > /tmp/parttable
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set_device_lock "${image_target}" \
512+
sfdisk -f "${image_target}" < /tmp/parttable
363513
}
364514

365515
function dump_local_image {
366516
local image_source=$1
367517
local image_target=$2
368-
local progress=$3
518+
local count=$3
519+
local block_size=$4
520+
local progress=$5
521+
if [ "${count}" -gt 0 ];then
522+
count="count=${count}"
523+
else
524+
unset count
525+
fi
526+
# shellcheck disable=SC2086
369527
if [ -e "${progress}" ];then
370528
(
371-
pv -n "${image_source}" | dd bs=32k of="${image_target}" &>/dev/null
529+
pv -n "${image_source}" |\
530+
dd bs="${block_size}" ${count} of="${image_target}" &>/dev/null
372531
) 2>"${progress}"
373532
else
374-
dd if="${image_source}" bs=32k of="${image_target}" &>/dev/null
533+
dd \
534+
if="${image_source}" bs="${block_size}" ${count} \
535+
of="${image_target}" &>/dev/null
375536
fi
376537
}
377538

378539
function dump_remote_image {
379540
local image_source=$1
380541
local image_target=$2
381-
local progress=$3
542+
local count=$3
543+
local block_size=$4
544+
local progress=$5
382545
local image_size
383546
image_size=$((blocks * blocksize))
547+
if [ "${count}" -gt 0 ];then
548+
count="count=${count}"
549+
else
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unset count
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fi
552+
# shellcheck disable=SC2086
384553
if [ -e "${progress}" ];then
385554
(
386555
fetch_file "${image_source}" "${image_size}" |\
387-
dd bs=32k of="${image_target}" &>/dev/null
556+
dd bs="${block_size}" ${count} of="${image_target}" &>/dev/null
388557
) 2>"${progress}"
389558
else
390559
fetch_file "${image_source}" |\
391-
dd bs=32k of="${image_target}" &>/dev/null
560+
dd bs="${block_size}" ${count} of="${image_target}" &>/dev/null
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fi
393562
}
394563

@@ -406,6 +575,13 @@ function check_image_integrity {
406575
# no verification wanted
407576
return
408577
fi
578+
if getargbool 0 rd.kiwi.install.retain_last; then
579+
if [ ! -e /tmp/retain_not_applicable ];then
580+
# no verification possible as only a portion of
581+
# the image got deployed intentionally
582+
return
583+
fi
584+
fi
409585
if command -v pv &>/dev/null && [ "${kiwi_oemsilentverify}" = "false" ]
410586
then
411587
# verify with dialog based progress information

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