Ubuntu 启动 systemd[1]：无法启动 casper-md5check 验证 Live ISO 校验和

Question

启动笔记本电脑时，会显示如下消息systemd[1]: Failed to start casper-md5check Verify Live ISO checksums.（取自journalctl -p err）并且\n systemctl status casper-md5check.service显示：

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\xc3\x97 casper-md5check.service - casper-md5check Verify Live ISO checksums\n     Loaded: loaded (/lib/systemd/system/casper-md5check.service; enabled; vendor preset: enabled)\n     Active: failed (Result: exit-code) since Sat 2022-07-30 09:24:42 EEST; 45min ago\n    Process: 787 ExecStart=/usr/lib/casper/casper-md5check /cdrom /cdrom/md5sum.txt (code=exited, status=1/FAILURE)\n   Main PID: 787 (code=exited, status=1/FAILURE)\n        CPU: 3ms\n\niul 30 09:24:42 AcerAspireV5-552G systemd[1]: Starting casper-md5check Verify Live ISO checksums...\niul 30 09:24:42 AcerAspireV5-552G casper-md5check[787]: .fopen md5_file: No such file or directory\niul 30 09:24:42 AcerAspireV5-552G casper-md5check[787]: Checking integrity, this may take some time (or try: fsck.mode=skip)\niul 30 09:24:42 AcerAspireV5-552G systemd[1]: casper-md5check.service: Main process exited, code=exited, status=1/FAILURE\niul 30 09:24:42 AcerAspireV5-552G systemd[1]: casper-md5check.service: Failed with result 'exit-code'.\niul 30 09:24:42 AcerAspireV5-552G systemd[1]: Failed to start casper-md5check Verify Live ISO checksums.\n

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我尝试运行sudo /usr/lib/casper/casper-md5check /cdrom /cdrom/md5sum.txt并得到以下结果：

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.\nChecking integrity, this may take some time (or try: fsck.mode=skip)\nfopen md5_file: No such file or directory\n

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错误代码为 1。

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编辑1

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我通过运行禁用了它的启动sudo systemctl disable casper-md5check.service。但这并不能回答问题是如何出现的。

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编辑2

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的内容/etc/lsb-release

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DISTRIB_ID=Ubuntu\nDISTRIB_RELEASE=22.04\nDISTRIB_CODENAME=jammy\nDISTRIB_DESCRIPTION="Linux Lite 6.0"\n

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Answer 1

运行systemctl --failed可能会产生类似于以下内容的输出，从而引导您访问此站点：

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UNIT                    LOAD   ACTIVE SUB    DESCRIPTION            \n\xe2\x97\x8f casper-md5check.service masked failed failed casper-md5check.service\n\nLOAD   = Reflects whether the unit definition was properly loaded.\nACTIVE = The high-level unit activation state, i.e. generalization of SUB.\nSUB    = The low-level unit activation state, values depend on unit type.\n1 loaded units listed.\n

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看来这是一个非关键错误，它已在 Ubuntu 22.04 (Jammy) 存储库中的 Linux Mint 21 (Vanessa) 世界中发现。

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$ lsb_release -a\n\nDistributor ID: Linuxmint\nDescription:    Linux Mint 21\nRelease:    21\nCodename:   vanessa\n

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运行apt-cache show casper以显示输出：

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Origin: Ubuntu\nFilename: pool/main/c/casper/casper_1.470_amd64.deb\nDescription-en: Run a "live" preinstalled system from read-only media\nDescription-md5: 9be0120948307c7e897a16c45a69ba0f\nTag: admin::boot, admin::filesystem, implemented-in::shell, protocol::smb,  role::plugin, scope::utility, special::completely-tagged, works-with-    format::iso9660\nTask: xubuntu-live\n

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这表明它来自 Ubuntu 主存储库。\n根据 pkg 描述和从 github 存储库文件casper-md5check.c收集的信息，如果您不涉及任何与实时启动安装相关的内容，则完全删除似乎是安全的。我删除了 casper 包sudo apt remove casper -y

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$ systemctl status casper-md5check显示该服务被屏蔽：

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\xc3\x97 casper-md5check.service\nLoaded: masked (Reason: Unit casper-md5check.service is masked.)\nActive: failed (Result: exit-code) since Mon 2022-09-26 23:25:24 PDT; 7min ago\nMain PID: 989 (code=exited, status=1/FAILURE)\nCPU: 1ms\n\nSep 26 23:25:24 LT-MINT2 systemd[1]: Starting casper-md5check Verify Live ISO checksums...\nSep 26 23:25:24 LT-MINT2 casper-md5check[989]: .fopen md5_file: No such file or directory\nSep 26 23:25:24 LT-MINT2 casper-md5check[989]: Checking integrity, this may take some time (or try: fsck.mode=skip)\nSep 26 23:25:24 LT-MINT2 systemd[1]: casper-md5check.service: Main process exited, code=exited, status=1/FAILURE\nSep 26 23:25:24 LT-MINT2 systemd[1]: casper-md5check.service: Failed with result \'exit-code\'.\nSep 26 23:25:24 LT-MINT2 systemd[1]: Failed to start casper-md5check Verify Live ISO checksums.\n

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使用自动取消屏蔽服务sudo systemctl unmask casper-md5check会删除位于 /etc/systemd/system/casper-md5check.service 的服务单元文件。

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然而，通过搜索“casper*”仍然发现了一些可以删除的 casper 相关文件：

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$ sudo rm /etc/systemd/system/casper.service\n$ sudo rm /etc/systemd/system/multi-user.target.wants/casper-md5check.service\n$ sudo rm /etc/systemd/system/final.target.wants/casper.service\n

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然后你可以sudo systemctl daemon-reload做sudo systemctl reset-failed来重置故障。

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$ systemctl --failed\n

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单元负载活动子描述\n列出了 0 个已加载单元。

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$ sudo systemctl is-system-running\n

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跑步

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