我遇到這個問題已經有一段時間了，所以今天我嘗試了我在網上找到的建議並運行systemd-analyze plot並檢查輸出。
我在這裡附加了 SVG 文件，因為除非我弄錯了，否則只有兩件事需要花費很長的時間來啟動，其中之一systemd-networkd-wait-online（當然），但後來，奇怪的是，sendmail我什至沒有在這台伺服器上使用它在我的家庭網路中，僅充當種子箱/媒體伺服器。
我在這裡錯過了什麼嗎？我wlan之前禁用了它以排除它，因為它是一台有線機器並且不需要wlan.
我禁用了sendmail，重新啟動，看著它超時，然後再次運行它，現在唯一需要時間的是我正在嘗試修復的事情。任何幫助將不勝感激。
https://c0ld.net/slowboot-nosendmail.svg
這是完整的journalctl：http://0x0.st/Xo36.txt
它有一個靜態 IP，不面向互聯網，運行plex, bittorrent-nox，jellyfin並且在啟動時安裝了幾個 USB 硬碟機用於存儲，這就是除了 和 之外正在運行的所有webmin內容cockpit。它安裝了完整的 Ubuntu GNome，但在啟動時不會啟動，如果我需要將它用作備用 PC，我只是想用它來娛樂一下。
我真的不想簡單地透過禁用服務來掩蓋問題。我什至嘗試更改為renderer: networkdfrom renderer: NetworkManagerinnetplan
旨在添加，輸出networkctl
1 lo loopback carrier unmanaged
2 eno1 ether routable configured
3 wlp1s0 wlan off unmanaged
3 links listed.
所以那裡沒什麼瘋狂的。
我還在optional: truenetplan中配置了eno1。
編輯：也嘗試新增 --any 和 --interface=eno1 ，如下指定，兩者仍然具有相同的逾時。 https://ubuntuforums.org/showthread.php?t=2490962
Apr 21 15:15:16 jays-lenovo systemd[1]: Starting Wait for Network to be Configured...
░░ Subject: A start job for unit systemd-networkd-wait-online.service has begun execution
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ A start job for unit systemd-networkd-wait-online.service has begun execution.
░░
░░ The job identifier is 3886.
Apr 21 15:17:16 jays-lenovo systemd-networkd-wait-online[4967]: Timeout occurred while waiting for network connectivity.
Apr 21 15:17:16 jays-lenovo systemd[1]: systemd-networkd-wait-online.service: Main process exited, code=exited, status=1/FAILURE
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ An ExecStart= process belonging to unit systemd-networkd-wait-online.service has exited.
░░
░░ The process' exit code is 'exited' and its exit status is 1.
Apr 21 15:17:16 jays-lenovo systemd[1]: systemd-networkd-wait-online.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ The unit systemd-networkd-wait-online.service has entered the 'failed' state with result 'exit-code'.
Apr 21 15:17:16 jays-lenovo systemd[1]: Failed to start Wait for Network to be Configured.
░░ Subject: A start job for unit systemd-networkd-wait-online.service has failed
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ A start job for unit systemd-networkd-wait-online.service has finished with a failure.
░░
░░ The job identifier is 3886 and the job result is failed.
這是在使用 --interface=eno1 重新啟動服務之後，這絕對是啟動的！
對 systemd-networkd.service 進行相同的檢查
-- Boot 984031206640442cb02a40798ddf3b7f --
Apr 21 14:21:12 jays-lenovo systemd[1]: Starting Network Configuration...
░░ Subject: A start job for unit systemd-networkd.service has begun execution
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ A start job for unit systemd-networkd.service has begun execution.
░░
░░ The job identifier is 49.
Apr 21 14:21:12 jays-lenovo systemd-networkd[1178]: lo: Link UP
Apr 21 14:21:12 jays-lenovo systemd-networkd[1178]: lo: Gained carrier
Apr 21 14:21:12 jays-lenovo systemd-networkd[1178]: Enumeration completed
Apr 21 14:21:12 jays-lenovo systemd[1]: Started Network Configuration.
░░ Subject: A start job for unit systemd-networkd.service has finished successfully
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ A start job for unit systemd-networkd.service has finished successfully.
░░
░░ The job identifier is 49.
Apr 21 14:23:15 jays-lenovo systemd-networkd[1178]: eno1: Link UP
Apr 21 14:23:18 jays-lenovo systemd-networkd[1178]: eno1: Gained carrier
Apr 21 14:23:19 jays-lenovo systemd-networkd[1178]: eno1: Gained IPv6LL
Apr 21 14:51:50 jays-lenovo systemd-networkd[1178]: eno1: Re-configuring with /run/systemd/network/10-netplan-eno1.network
Apr 21 14:51:51 jays-lenovo systemd-networkd[1178]: eno1: Re-configuring with /run/systemd/network/10-netplan-eno1.network
Apr 21 14:51:51 jays-lenovo systemd-networkd[1178]: eno1: DHCPv6 lease lost
Apr 21 14:52:23 jays-lenovo systemd[1]: Stopping Network Configuration...
░░ Subject: A stop job for unit systemd-networkd.service has begun execution
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ A stop job for unit systemd-networkd.service has begun execution.
░░
░░ The job identifier is 4966.
Apr 21 14:52:23 jays-lenovo systemd-networkd[1178]: eno1: DHCPv6 lease lost
Apr 21 14:52:23 jays-lenovo systemd[1]: systemd-networkd.service: Deactivated successfully.
░░ Subject: Unit succeeded
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ The unit systemd-networkd.service has successfully entered the 'dead' state.
Apr 21 14:52:23 jays-lenovo systemd[1]: Stopped Network Configuration.
░░ Subject: A stop job for unit systemd-networkd.service has finished
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ A stop job for unit systemd-networkd.service has finished.
░░
░░ The job identifier is 4966 and the job result is done.
-- Boot dc2cb94cb1f649c49648ba8e085192db --
Apr 21 14:53:19 jays-lenovo systemd[1]: Starting Network Configuration...
░░ Subject: A start job for unit systemd-networkd.service has begun execution
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ A start job for unit systemd-networkd.service has begun execution.
░░
░░ The job identifier is 25.
Apr 21 14:53:19 jays-lenovo systemd-networkd[1172]: lo: Link UP
Apr 21 14:53:19 jays-lenovo systemd-networkd[1172]: lo: Gained carrier
Apr 21 14:53:19 jays-lenovo systemd-networkd[1172]: Enumeration completed
Apr 21 14:53:19 jays-lenovo systemd[1]: Started Network Configuration.
░░ Subject: A start job for unit systemd-networkd.service has finished successfully
░░ Defined-By: systemd
░░ Support: http://www.ubuntu.com/support
░░
░░ A start job for unit systemd-networkd.service has finished successfully.
░░
░░ The job identifier is 25.
Apr 21 14:53:19 jays-lenovo systemd-networkd[1172]: eno1: Link UP
Apr 21 14:53:22 jays-lenovo systemd-networkd[1172]: eno1: Gained carrier
Apr 21 14:53:24 jays-lenovo systemd-networkd[1172]: eno1: Gained IPv6LL
Apr 21 15:26:32 jays-lenovo systemd-networkd[1172]: eno1: Re-configuring with /run/systemd/network/10-netplan-eno1.network
Apr 21 15:26:32 jays-lenovo systemd-networkd[1172]: eno1: DHCPv6 lease lost
Apr 21 15:26:32 jays-lenovo systemd-networkd[1172]: eno1: Re-configuring with /run/systemd/network/10-netplan-eno1.network
Apr 21 15:26:32 jays-lenovo systemd-networkd[1172]: eno1: DHCPv6 lease lost
滿的https://c0ld.net/dmesg.html可以在這裡找到。我現在不知道還能嘗試什麼，我已經在網路上搜尋過了。
eno1 也配置為靜態 IP，因此花費更長的時間而不是更短的時間變得可用是沒有意義的。
192.168.2.1是我整個家庭的主路由器，有多個不同的路由器和數十台設備，其他任何一個都沒有任何問題。
# This is the network config written by 'subiquity'
network:
version: 2
renderer: networkd
ethernets:
eno1:
optional: false
addresses:
- 192.168.2.99/24
nameservers:
addresses: [192.168.2.1]
routes:
- to: default
via: 192.168.2.1
答案1
哦，哇，好吧，做了一些練習，對於未來的旅行者來說，這是 NetworkManager 和 netplan 以及網路的混亂。我去遵循了這兩個（或無論如何都丟失了一些位元），一切都很完美，幾秒鐘重新啟動:)
https://linux.fernandocejas.com/docs/how-to/switch-from-network-manager-to-systemd-networkd
https://askubuntu.com/questions/1336247/removing-netplan-to-use-systemd-networkd-directly