From d1c0fdb2b321d2c1845a338933ebac9b6db7d229 Mon Sep 17 00:00:00 2001 From: Juan Cruz Viotti Date: Wed, 20 Jul 2016 11:33:20 -0400 Subject: [PATCH] docs: ubuntu iso's hybrid format and parted warnings (#585) Document that `parted` warnings about invalid GPT and physical block size issues can be safely ignored as they are a consequence of "hybrid iso's". Fixes: https://github.com/resin-io/etcher/issues/312 Signed-off-by: Juan Cruz Viotti --- docs/USER-DOCUMENTATION.md | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/docs/USER-DOCUMENTATION.md b/docs/USER-DOCUMENTATION.md index 943e5ab2..46751c4b 100644 --- a/docs/USER-DOCUMENTATION.md +++ b/docs/USER-DOCUMENTATION.md @@ -16,4 +16,35 @@ To deactivate this feature, `touch` any of the files listed below: - `/usr/share/appimagekit/no_desktopintegration` - `/etc/appimagekit/no_desktopintegration` +Flashing Ubuntu ISOs +-------------------- + +Ubuntu images (and potentially some other related GNU/Linux distributions) have +a peculiar format that allows the image to boot without any further +modification from both CDs and USB drives. + +A consequence of this enhancement is that some programs, like `parted` get +confused about the drive's format and partition table, printing warnings such +as: + +> /dev/xxx contains GPT signatures, indicating that it has a GPT table. +> However, it does not have a valid fake msdos partition table, as it should. +> Perhaps it was corrupted -- possibly by a program that doesn't understand GPT +> partition tables. Or perhaps you deleted the GPT table, and are now using an +> msdos partition table. Is this a GPT partition table? Both the primary and +> backup GPT tables are corrupt. Try making a fresh table, and using Parted's +> rescue feature to recover partitions. + +*** + +> Warning: The driver descriptor says the physical block size is 2048 bytes, +> but Linux says it is 512 bytes. + +All these warnings are **safe to ignore**, and your drive should be able to +boot without any problems. + +Refer to [the following message from Ubuntu's mailing +list](https://lists.ubuntu.com/archives/ubuntu-devel/2011-June/033495.html) if +you want to learn more. + [appimage]: http://appimage.org