• Get Chrome OS Flex for PC or Mac - Chrome Enterprise

ChromeのextentionでUSBメモリに書き込むらしい

• Chromebook リカバリ ユーティリティ - Chrome ウェブストア

しかしLinux環境ではダメらしい．

イメージデータさえ入手できればddあたりで書き込みできるのではと探す．

• The extension just downloads a .bin file from Google and writes it onto the USB ... | Hacker News

The manifest URL is https://dl.google.com/dl/edgedl/chromeos/recovery/cloudready...

マニフェストjsonファイルがあるのでこの中を見るとそれらしいものが書かれている．

$ curl -s https://dl.google.com/dl/edgedl/chromeos/recovery/cloudready_recovery.json
[
  {
    "channel": "dev-channel",
    "desc": "",
    "file": "chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin",
    "filesize": 6939566592,
    "hwidmatch": "^REVEN($| .*)",
    "manufacturer": "Google Chrome OS Flex",
    "md5": "7d91cf099c5d7bb33e66cab8cf56a23f",
    "model": "Chrome OS Flex (Developer-Unstable)",
    "name": "Chrome OS Flex (Developer-Unstable)",
    "photourl": "",
    "sha1": "b11edcd9ef35ec24a9fcb3d9f4e6c507d3da3637",
    "sku": "",
    "url": "https://dl.google.com/dl/edgedl/chromeos/recovery/chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin.zip",
    "version": "14516.0.0",
    "zipfilesize": 1095476192,
    "chrome_version": "100.0.4880.0",
    "hwids": []
  }

.[].url をダウンロード

$ wget -c $( curl -s https://dl.google.com/dl/edgedl/chromeos/recovery/cloudready_recovery.json | jq -r .[].url )
$ ls -s chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin.zip
1069804 chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin.zip

チェックサムの確認．(md5やsha1なのか)

$ sha1sum  ./chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin.zip 
b11edcd9ef35ec24a9fcb3d9f4e6c507d3da3637  ./chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin.zip
$ md5sum  ./chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin.zip 
7d91cf099c5d7bb33e66cab8cf56a23f  ./chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin.zip

PCにターゲットのUSBメモリを差し込む前にdmesgを起動しておいて

$ sudo dmesg -Hw

差し込んだときのメッセージを確認してデヴァイス名を確認．ここでは sdb ．確認したらCtrl+cでdmesg終了

[  +0.000007] usb 4-2: New USB device strings: Mfr=3, Product=4, SerialNumber=5
[  +0.000002] usb 4-2: Product: Transcend                                                                                                                                        [  +0.000001] usb 4-2: Manufacturer: TS-RDF5  
[  +0.000001] usb 4-2: SerialNumber: 000000000037                           
[  +0.002415] usb-storage 4-2:1.0: USB Mass Storage device detected
[  +0.000165] scsi host6: usb-storage 4-2:1.0
[  +1.030606] scsi 6:0:0:0: Direct-Access     TS-RDF5  SD  Transcend    TS3A PQ: 0 ANSI: 6
[  +0.000389] sd 6:0:0:0: Attached scsi generic sg2 type 0                                                                                                                       [  +0.335897] sd 6:0:0:0: [sdb] 125173760 512-byte logical blocks: (64.1 GB/59.7 GiB)
[  +0.000722] sd 6:0:0:0: [sdb] Write Protect is off                                                                                                                             
[  +0.000005] sd 6:0:0:0: [sdb] Mode Sense: 23 00 00 00                     
[  +0.000784] sd 6:0:0:0: [sdb] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[  +0.011296]  sdb: sdb1

確認したデバイスに解凍しつつ書き込み．

$ zcat ./chromeos_14516.0.0_reven_recovery_dev-channel_mp-v2.bin.zip | sudo dd of=/dev/sdb bs=8M conv=fsync status=progress