Minimal ISO:
1m21 -> 2m25
625M -> 617M
Plasma5 ISO:
2m45 -> 5m18
1.4G -> 1.3G
Decompression speed stays about the same. It's just a few seconds for the whole
image anyways and, with that kind of speed, you're going to be bottlenecked by
IO long before the CPU.
Prior to this commit, installation over serial console would requiring
manually having to modify the kernel modeline, as described in
https://github.com/NixOS/nixpkgs/issues/58198 .
This is unnecessarily fiddly, so this commit adds a syslinux boot
entry that has serial enabled.
GRUB already has a serial console entry:
2c07a0800a/nixos/modules/installer/cd-dvd/iso-image.nix (L311-L317)
Why 115200 bps? This is already used in other places, e.g. https://github.com/NixOS/nixpkgs/pull/58196
I tested this change by building the image, booting the image, and
observing the boot process over serial:
$ cd nixos/
$ nix-build -A config.system.build.isoImage -I nixos-config=modules/installer/cd-dvd/installation-cd-minimal.nix default.nix
$ sudo cp /nix/store/arcl702c3z8xlndlvnfplq9yhixjvs9k-nixos-20.09pre-git-x86_64-linux.iso/iso/nixos-20.09pre-git-x86_64-linux.iso /dev/sdb
$ picocom -b 115200 /dev/ttyUSB0
we use stdenv.hostPlatform.uname.processor, which I believe is just like
`uname -p`.
Example values:
```
(import <nixpkgs> { system = "x86_64-linux"; }).stdenv.hostPlatform.uname.processor
"x86_64"
(import <nixpkgs> { system = "aarch64-linux"; }).stdenv.hostPlatform.uname.processor
aarch64
(import <nixpkgs> { system = "armv7l-linux"; }).stdenv.hostPlatform.uname.processor
"armv7l"
```
The volumeID will now be in the format of:
nixos-$EDITON-$RELEASE-$ARCH
an example for the minimal image would look like:
nixos-minimal-20.09-x86-64-linux
In 87a19e9048 I merged staging-next into master using the GitHub gui as intended.
In ac241fb7a5 I merged master into staging-next for the next staging cycle, however, I accidentally pushed it to master.
Thinking this may cause trouble, I reverted it in 0be87c7979. This was however wrong, as it "removed" master.
This reverts commit 0be87c7979.
I merged master into staging-next but accidentally pushed it to master.
This should get us back to 87a19e9048.
This reverts commit ac241fb7a5, reversing
changes made to 76a439239e.
When 'grafting' '/nix/store/<hash>-loopback.cfg' from disk onto
'/boot/grub/loopback.cfg' on the iso, the parent 'grub' directory does not
exist yet. In this case it is automatically created and inherits its
attributes, including timestamp, from /nix/store.
This is correct/expected/intentional behavior of xorriso, but has the
undesired result of leaking the timestamps of /nix/store into the iso. For
this reason we put the loopback.cfg in a
'/nix/store/<hash>-loopback.cfg/grub/loopback.cfg' instead, so it will inherit
the attributes from the correctly-timestamped
'/nix/store/<hash>-loopback.cfg/grub' directory.
For the same reason we move '/EFI/boot/efi-background.png' down in the list
so it is grafted after its parent '/EFI/boot' directory is created with
the correct timestamp.
fixes#74944
Prior to this commit an installation over serial via syslinux would
involve:
1. setting bitrate to BIOS's bitrate (typically 115200)
2. setting bitrate to syslinux's bitrate (38400)
3. setting bitrate to stty's bitrate (115200)
By changing syslinux's bitrate to 115200, an installation over serial
is a smoother experience, and consistent with the GRUB2 installation
which is also 115200 bps.
[root@nixos:~]# stty
speed 115200 baud; line = 0;
-brkint ixoff iutf8
-iexten
In a future commit I will add default serial terminals to the syslinux
kernel lines.
```
b Batch mode. Optimized for huge recursive copies, but less secure if a crash happens during the copy.
```
It seems the "less secure if a crash happens" does not need a crash to
happen.
With batch mode:
```
/[...]/.
Start (0) does not point to parent (___)
```
For pretty much everything copied in.
Without batch mode, everything passes `fsck`.
See #51150
This is a 277K (as of right now) addition that can greatly help in some
last recourse scenarios. The specific rEFInd setup will not be able to
boot the installer image, but this is not why it has been added. It has
been added to make use of its volumes scanning capabilities to boot
existing EFI images on the target computer, which is sometimes necessary
with buggy EFI. While is isn't NixOS's job to fix buggy EFI, shipping
this small bit with the installer will help the unlucky few.
Example scenario: two wildly different EFI implementation I have
encountered have fatal flaws in which they sometimes will lose all the
settings, this includes boot configuration. This is compounded by the
fact that the two specific and distinct implementation do not allow
manually adding ESP paths from their interface. The only recourse is to
let the EFI boot the default paths, EFI/boot/boot{platform}.efi, which
is not a default location used by the NixOS bootloaders. rEFInd is able
to scan the volumes and detect the existing efi bootloaders, and boot
them successfully.
Following up https://github.com/NixOS/nixpkgs/pull/23665
Bootable USB-drives are not limited to ISO-images, there can be "normal" MBR/GPT-partitioned disk connected via USB-rack.
Also, "uas" implies "usb-storage", so there is no need to mention both.
Add another option for debugging instead. Lots of users have been
complaining about this default behaviour.
This patch also cleans up the EFI bootloader entries in the ISO.
