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--- doc:appunti:linux:sa:if_rename [2024/06/21 17:48] – [With Debian 10 Buster] niccolo
+++ doc:appunti:linux:sa:if_rename [2024/06/21 17:54] (current) – [Beware of initramfs image] niccolo
@@ Line 29: / Line 29: @@
 ==== Beware of initramfs image ====
-If you have some files in **/etc/systemd/network/** to rename network interfaces and you update the **initramfs image** (e.g. by running the **update-initramfs** tool), a copy of these files are placed into the image itself (under the path **usr/lib/systemd/network/**).
+:!: If you have some files in **/etc/systemd/network/** to rename network interfaces and you update the **initramfs image** (e.g. by running the **update-initramfs** tool), a copy of these files are placed into the image itself (under the path **usr/lib/systemd/network/**).
 These files are considered by ''init'' before it considers the content of **/etc/systemd/network/**. When the latter files are processed, some renaming may have already occurred and rules may not longer apply or may fail.
@@ Line 41: / Line 41: @@
 === How to unpack the iniramfs image to inspect its content ===
-In Debian 12 the iniramfs image is composed by a cpio archive containing the Intel microcode followed by the Zstandard compressed cpio archive of the initramfs. To extract both, do the following:
+In **Debian 12** the iniramfs image may be composed by two appended cpio archives. The first containing the Intel microcode in //ASCII cpio archive// format, and the second containing the actual initramfs as a //Zstandard compressed cpio archive//. To extract both, do the following:
+Extract **the microcode part** (take note of the number of blocks printed on stderr):
-Extract the microcode (take note of the number of blocks printed on stderr):
 <code>
@@ Line 51: / Line 50: @@
 </code>
-Make a copy of initramfs stripping the microcode and decompress it:
+Make a copy of **the initramfs part** stripping the microcode and decompress it:
 <code>
-dd if=/boot/initrd.img-6.1.0-21-amd64 of=initramfs.img.zstd bs=512 skip=14080
+dd if=/boot/initrd.img-6.1.0-21-amd64 of=initramfs.img.zst bs=512 skip=14080
-unzstd initramfs.img.zstd --stdout | cpio --extract --make-directories  --no-absolute-filenames
+unzstd initramfs.img.zst --stdout | cpio --extract --make-directories  --no-absolute-filenames
 </code>