docker启动失败原因

1.docker启动失败

root@localhost:~# systemctl daemon-reload && systemctl restart docker.service
Job for docker.service failed because the control process exited with error code.
See "systemctl status docker.service" and "journalctl -xe" for details.
root@localhost:~# systemctl status docker.service
● docker.service - Docker Application Container Engine
   Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
  Drop-In: /etc/systemd/system/docker.service.d
           └─override.conf
   Active: failed (Result: exit-code) since Fri 2020-09-04 09:31:26 CST; 4s ago
     Docs: https://docs.docker.com
  Process: 19628 ExecStart=/usr/bin/dockerd -H unix:// -H tcp://127.0.0.1:2375 (code=exited, status=1/FAILURE)
 Main PID: 19628 (code=exited, status=1/FAILURE)

Sep 04 09:31:26 kuaiyue systemd[1]: docker.service: Service hold-off time over, scheduling restart.
Sep 04 09:31:26 kuaiyue systemd[1]: docker.service: Scheduled restart job, restart counter is at 3.
Sep 04 09:31:26 kuaiyue systemd[1]: Stopped Docker Application Container Engine.
Sep 04 09:31:26 kuaiyue systemd[1]: docker.service: Start request repeated too quickly.
Sep 04 09:31:26 kuaiyue systemd[1]: docker.service: Failed with result 'exit-code'.
Sep 04 09:31:26 kuaiyue systemd[1]: Failed to start Docker Application Container Engine.

各种网页查找“docker.service: Service hold-off time over, scheduling restart”，然后并没有找到解决办法！

有说/etc/docker/daemon.json 格式不对，有说/etc/docker/daemon.json 改为/etc/docker/daemon.conf，都没有任何作用。

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最后找到原因的办法是，启动docker以后，立即执行journalctl -xe或者systemctl status docker.service，找到docker出错的原因。

如果journalctl -xe/systemctl status docker.service执行慢了，只能看到下面这样的

-- 
-- The result is RESULT.
Sep 04 09:31:26 systemd[1]: docker.service: Service hold-off time over, scheduling restart.
Sep 04 09:31:26 systemd[1]: docker.service: Scheduled restart job, restart counter is at 3.
-- Subject: Automatic restarting of a unit has been scheduled
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Automatic restarting of the unit docker.service has been scheduled, as the result for
-- the configured Restart= setting for the unit.
Sep 04 09:31:26 systemd[1]: Stopped Docker Application Container Engine.
-- Subject: Unit docker.service has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.service has finished shutting down.
Sep 04 09:31:26 systemd[1]: Closed Docker Socket for the API.
-- Subject: Unit docker.socket has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.socket has finished shutting down.
Sep 04 09:31:26 systemd[1]: Stopping Docker Socket for the API.
-- Subject: Unit docker.socket has begun shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.socket has begun shutting down.
Sep 04 09:31:26 systemd[1]: Starting Docker Socket for the API.
-- Subject: Unit docker.socket has begun start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.socket has begun starting up.
Sep 04 09:31:26 systemd[1]: Listening on Docker Socket for the API.
-- Subject: Unit docker.socket has finished start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.socket has finished starting up.
-- 
-- The start-up result is RESULT.
Sep 04 09:31:26 systemd[1]: docker.service: Start request repeated too quickly.
Sep 04 09:31:26 systemd[1]: docker.service: Failed with result 'exit-code'.
Sep 04 09:31:26 systemd[1]: Failed to start Docker Application Container Engine.
-- Subject: Unit docker.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.service has failed.
-- 
-- The result is RESULT.
Sep 04 09:31:26 systemd[1]: docker.socket: Failed with result 'service-start-limit-hit'.

上面没有说明出错原因。

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下面这个才写出了出错原因。 systemctl status docker.service

root@localhost:~# systemctl status docker.service
● docker.service - Docker Application Container Engine
   Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
  Drop-In: /etc/systemd/system/docker.service.d
           └─override.conf
   Active: activating (start) since Fri 2020-09-04 09:37:33 CST; 565ms ago
     Docs: https://docs.docker.com
 Main PID: 22738 (dockerd)
    Tasks: 9
   CGroup: /system.slice/docker.service
           └─22738 /usr/bin/dockerd -H unix:// -H tcp://127.0.0.1:2375

Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.445359792Z" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0x44205ee0e0, CONNECTING" module=grpc
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.446973762Z" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0x44205ee0e0, READY" module=grpc
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.447462812Z" level=info msg="ccResolverWrapper: sending new addresses to cc: [{unix:///run/containerd/containerd.sock 0  }]" module=grpc
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.447526483Z" level=info msg="ClientConn switching balancer to \"pick_first\"" module=grpc
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.447668423Z" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0x44205ee3f0, CONNECTING" module=grpc
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.448877970Z" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0x44205ee3f0, READY" module=grpc
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.453395805Z" level=info msg="[graphdriver] using prior storage driver: overlay2"
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.468522766Z" level=info msg="Graph migration to content-addressability took 0.00 seconds"
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.471128434Z" level=info msg="Loading containers: start."
Sep 04 09:37:33 dockerd[22738]: time="2020-09-04T01:37:33.498476011Z" level=warning msg="Running modprobe xt_conntrack failed with message: `modprobe: ERROR: could not insert 'xt_conntrack': Exec format error\ninsmod /lib/modules

或者

root@localhost:~# journalctl -xe
-- Subject: Unit docker.socket has finished start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.socket has finished starting up.
-- Support: http://www.ubuntu.com/support
-- 
-- Automatic restarting of the unit docker.service has been scheduled, as the result for
-- the configured Restart= setting for the unit.
Sep 03 17:02:09 localhost systemd[1]: Stopped Docker Application Container Engine.
-- Subject: Unit docker.service has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.service has finished shutting down.
Sep 03 17:02:09 localhost systemd[1]: Closed Docker Socket for the API.
-- Subject: Unit docker.socket has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.socket has finished shutting down.
Sep 03 17:02:09 localhost systemd[1]: Stopping Docker Socket for the API.
-- Subject: Unit docker.socket has begun shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.socket has begun shutting down.
Sep 03 17:02:09 localhost systemd[1]: Starting Docker Socket for the API.
-- Subject: Unit docker.socket has begun start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.socket has begun starting up.
Sep 03 17:02:09 localhost systemd[1]: Listening on Docker Socket for the API.
-- 
-- The start-up result is RESULT.
Sep 03 17:02:09 localhost systemd[1]: Starting Docker Application Container Engine...
-- Subject: Unit docker.service has begun start-up
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
-- 
-- Unit docker.service has begun starting up.
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.110222230Z" level=warning msg="[!] DON'T BIND ON ANY IP ADDRESS WITHOUT setting --tlsverify IF YOU DON'T KNOW WHAT YOU'RE DOING [!]"
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.116773985Z" level=info msg="systemd-resolved is running, so using resolvconf: /run/systemd/resolve/resolv.conf"
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.118918145Z" level=info msg="parsed scheme: \"unix\"" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.118994581Z" level=info msg="scheme \"unix\" not registered, fallback to default scheme" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.119106894Z" level=info msg="parsed scheme: \"unix\"" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.119299004Z" level=info msg="scheme \"unix\" not registered, fallback to default scheme" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.120061161Z" level=info msg="ccResolverWrapper: sending new addresses to cc: [{unix:///run/containerd/containerd.sock 0  }]" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.122263838Z" level=info msg="ClientConn switching balancer to \"pick_first\"" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.123354778Z" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0x442015b950, CONNECTING" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.125152357Z" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0x442015b950, READY" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.126387488Z" level=info msg="ccResolverWrapper: sending new addresses to cc: [{unix:///run/containerd/containerd.sock 0  }]" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.126982855Z" level=info msg="ClientConn switching balancer to \"pick_first\"" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.127383233Z" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0x442015bc40, CONNECTING" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.128749117Z" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0x442015bc40, READY" module=grpc
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.129671905Z" level=info msg="[graphdriver] using prior storage driver: overlay2"
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.140991314Z" level=info msg="Graph migration to content-addressability took 0.00 seconds"
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.144513158Z" level=info msg="Loading containers: start."
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.164800986Z" level=warning msg="Running modprobe xt_conntrack failed with message: `modprobe: ERROR: could not insert 'xt_conntrack': ExSep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.140991314Z" level=info msg="Graph migration to content-addressability took 0.00 seconds"
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.144513158Z" level=info msg="Loading containers: start."
Sep 03 17:02:10 localhost dockerd[13483]: time="2020-09-03T09:02:10.164800986Z" level=warning msg="Running modprobe xt_conntrack failed with message: `modprobe: ERROR: could not insert 'xt_conntrack': Exec format error\ninsmod /lib/modul

根据上面的信息可以看到是加载内核模块xt_conntrack出错了。

至于加载失败的原因，我这边是缺少xt_conntrack模块，导致加载失败。

在网上看到另一种原因，xt_conntrack有，但是也加载失败了，

原因是xt_conntrack模块被加入到黑名单里面了。

重新编译内核，自动加载xt_conntrack，或者手动加载xt_conntrack以后，再启动docker，就没有报错了。