[500XRP悬赏] OpenVZ ubuntu10.04 中 SSH 无法启动的问题

一台 OpenVZ 的 VPS ，在重启后 SSH 服务无法启动，仅能通过管理后台使用 “Serial Console” 登录

目前出问题的 VPS 的所有进程：
root@ssd:/# ps auxf
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 1.0 2504 1360 ? Ss 09:50 0:00 init
root 2 0.0 0.0 0 0 ? S 09:50 0:00 [kthreadd/1980]
root 3 0.0 0.0 0 0 ? S 09:50 0:00 \_ [khelper/1980]
root 270 0.0 0.6 2336 884 ? Ss 09:50 0:00 cron
root 354 0.0 0.5 27496 760 ? Ss 09:51 0:00 vzctl: pts/0
root 355 0.0 1.2 3004 1644 pts/0 Ss 09:51 0:00 \_ -bash
root 367 0.0 0.6 2392 856 pts/0 R+ 09:51 0:00 \_ ps auxf

root@ssd:/# netstat -nl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
Active UNIX domain sockets (only servers)
Proto RefCnt Flags Type State I-Node Path
unix 2 [ ACC ] STREAM LISTENING 2875821005 @/com/ubuntu/upstart

尝试 ssh restart 与 ssh start 均无法启动 ssh 服务：

root@ssd:/# /etc/init.d/ssh restart
Rather than invoking init scripts through /etc/init.d, use the service(8)
utility, e.g. service ssh restart

Since the script you are attempting to invoke has been converted to an
Upstart job, you may also use the restart(8) utility, e.g. restart ssh
ssh stop/pre-start, process 386

root@ssd:/# /etc/init.d/ssh start
Rather than invoking init scripts through /etc/init.d, use the service(8)
utility, e.g. service ssh start

Since the script you are attempting to invoke has been converted to an
Upstart job, you may also use the start(8) utility, e.g. start ssh
ssh stop/pre-start, process 399

root@ssd:/# netstat -nl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
Active UNIX domain sockets (only servers)
Proto RefCnt Flags Type State I-Node Path
unix 2 [ ACC ] STREAM LISTENING 2875821005 @/com/ubuntu/upstart

安装 dropbear 在其他端口，并启动，同样无法启动：
root@ssd:~# /etc/init.d/dropbear start
Starting Dropbear SSH server: dropbear.

root@ssd:~# netstat -nl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
Active UNIX domain sockets (only servers)
Proto RefCnt Flags Type State I-Node Path
unix 2 [ ACC ] STREAM LISTENING 2875821005 @/com/ubuntu/upstart

-----------------------------------------------------------------------------------------------------

这个问题多次出现在 OpenVZ 的 ubuntu VPS 中，都是正常使用时，重启系统后 SSH 无法启动，参考帖子：
http://lowendtalk.com/discussion/9076/weird-can-t-start-ssh-service-on-a-openvz-vps

始终没有任何办法能解决，最后都是重新安装系统
（但同样的问题从未出现在 KVM / XEN 架构的 VPS，仅出现在 OpenVZ）

如果能帮助我，或者引导我通过查看日志之类的最终能解决问题，我愿意赠送 500XRP 表示感谢
感谢各位！：）

andybest

2014-01-07 13:23:11 +08:00

@lijinma 谢谢，是Ubuntu 10.04 server，没有这个文件：
root@ssd:/# cat /var/log/secure
cat: /var/log/secure: No such file or directory

juicy

2014-01-07 13:25:28 +08:00

@andybest log的问题你看看/etc/ssh/sshd_config 这个文件下的logLevel有没有设置成Quiet，也许是这个原因

lijinma

2014-01-07 13:28:05 +08:00

@andybest 噢，不好意思，没看到；

那你enable一下log:

sudo service rsyslog restart
或者
/etc/init.d/syslog restart

然后看一下：/etc/syslog.conf 里面应该有：

`auth,authpriv.* /var/log/auth.log`

类似的配置；

andybest

2014-01-07 13:34:44 +08:00

@juicy 检查了，是默认的：
LogLevel INFO

juicy

2014-01-07 13:50:42 +08:00

执行/usr/sbin/sshd -d的时候
返回Missing privilege separation directory: /var/run/sshd
这里应该是有问题的，我尝试了一下用自己的机子，没有发现这条提示

当楼主运行
mkdir /var/run/sshd
chmod 0755 /var/run/sshd
之后，
楼主可否再执行一下/usr/sbin/sshd -d

andybest

2014-01-07 13:53:37 +08:00

@lijinma 谢谢，奇怪的是syslog无法安装和启动：

root@ssd:/# sudo service rsyslog restart
rsyslog: unrecognized service
root@ssd:/#
root@ssd:/# service rsyslog restart
rsyslog: unrecognized service
root@ssd:/#
root@ssd:/# /etc/init.d/syslog restart
-bash: /etc/init.d/syslog: No such file or directory
root@ssd:/#
root@ssd:/# apt-get install syslog
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Couldn't find package syslog
root@ssd:/#
root@ssd:/# apt-get install syslogd
Reading package lists... Done
Building dependency tree
Reading state information... Done
Note, selecting sysklogd instead of syslogd
The following extra packages will be installed:
klogd sysklogd
The following NEW packages will be installed:
klogd sysklogd
0 upgraded, 2 newly installed, 0 to remove and 47 not upgraded.
Need to get 0B/116kB of archives.
After this operation, 369kB of additional disk space will be used.
Do you want to continue [Y/n]? y

Selecting previously deselected package sysklogd.
(Reading database ... 26840 files and directories currently installed.)
Unpacking sysklogd (from .../sysklogd_1.5-5ubuntu4_i386.deb) ...
Selecting previously deselected package klogd.
Unpacking klogd (from .../klogd_1.5-5ubuntu4_i386.deb) ...
Processing triggers for man-db ...
Setting up sysklogd (1.5-5ubuntu4) ...
* Starting system log daemon...
...done.

Setting up klogd (1.5-5ubuntu4) ...
* Starting kernel log daemon...

...fail!

root@ssd:/#

andybest

2014-01-07 13:58:41 +08:00

@juicy 牛！！！！！启动了：

root@ssd:/# mkdir /var/run/sshd
mkdir: cannot create directory `/var/run/sshd': File exists
root@ssd:/#
root@ssd:/# chmod 0755 /var/run/sshd

root@ssd:/# /usr/sbin/sshd -d
debug1: sshd version OpenSSH_5.3p1 Debian-3ubuntu7
debug1: read PEM private key done: type RSA
debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048
debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048
debug1: private host key: #0 type 1 RSA
debug1: read PEM private key done: type DSA
debug1: Checking blacklist file /usr/share/ssh/blacklist.DSA-1024
debug1: Checking blacklist file /etc/ssh/blacklist.DSA-1024
debug1: private host key: #1 type 2 DSA
debug1: rexec_argv[0]='/usr/sbin/sshd'
debug1: rexec_argv[1]='-d'
debug1: Bind to port 22 on 0.0.0.0.
Server listening on 0.0.0.0 port 22.
debug1: Bind to port 22 on ::.
Server listening on :: port 22.

可以SSH连接了，在22端口，如何恢复SSH服务？

juicy

2014-01-07 14:01:15 +08:00

@andybest

那太好了！！ Ctrl-C退出当前debugger模式，按正常方式启动就可以了吧

andybest

2014-01-07 14:04:54 +08:00

@juicy

使用：

root@ssd:/# /etc/init.d/ssh start
Rather than invoking init scripts through /etc/init.d, use the service(8)
utility, e.g. service ssh start

Since the script you are attempting to invoke has been converted to an
Upstart job, you may also use the start(8) utility, e.g. start ssh
ssh stop/pre-start, process 994

仍然无法启动 ssh 服务，不过 auth.log 有日志了！

root@ssd:/# tail /var/log/auth.log

Jan 7 08:14:38 ssd groupadd[578]: group added to /etc/group: name=klog, GID=111
Jan 7 08:14:38 ssd groupadd[578]: group added to /etc/gshadow: name=klog
Jan 7 08:14:38 ssd groupadd[578]: new group: name=klog, GID=111
Jan 7 08:14:38 ssd useradd[582]: new user: name=klog, UID=107, GID=111, home=/home/klog, shell=/bin/false
Jan 7 08:14:38 ssd usermod[587]: change user 'klog' password
Jan 7 08:14:38 ssd chage[592]: changed password expiry for klog
Jan 7 08:15:01 ssd CRON[622]: pam_unix(cron:session): session opened for user root by (uid=0)
Jan 7 08:15:01 ssd CRON[622]: pam_unix(cron:session): session closed for user root
Jan 7 08:25:01 ssd CRON[651]: pam_unix(cron:session): session opened for user root by (uid=0)
Jan 7 08:25:01 ssd CRON[651]: pam_unix(cron:session): session closed for user root
Jan 7 08:35:01 ssd CRON[658]: pam_unix(cron:session): session opened for user root by (uid=0)
Jan 7 08:35:01 ssd CRON[658]: pam_unix(cron:session): session closed for user root
Jan 7 08:36:01 ssd CRON[663]: pam_unix(cron:session): session opened for user root by (uid=0)
Jan 7 08:36:01 ssd CRON[663]: pam_unix(cron:session): session closed for user root
Jan 7 08:45:01 ssd CRON[668]: pam_unix(cron:session): session opened for user root by (uid=0)
Jan 7 08:45:01 ssd CRON[668]: pam_unix(cron:session): session closed for user root
Jan 7 08:55:01 ssd CRON[675]: pam_unix(cron:session): session opened for user root by (uid=0)
Jan 7 13:55:01 ssd CRON[940]: pam_unix(cron:session): session closed for user root
Jan 7 13:57:12 ssd sshd[947]: debug1: sshd version OpenSSH_5.3p1 Debian-3ubuntu7
Jan 7 13:57:12 ssd sshd[947]: debug1: read PEM private key done: type RSA
Jan 7 13:57:12 ssd sshd[947]: debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048
Jan 7 13:57:12 ssd sshd[947]: debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048
Jan 7 13:57:12 ssd sshd[947]: debug1: private host key: #0 type 1 RSA
Jan 7 13:57:12 ssd sshd[947]: debug1: read PEM private key done: type DSA
Jan 7 13:57:12 ssd sshd[947]: debug1: Checking blacklist file /usr/share/ssh/blacklist.DSA-1024
Jan 7 13:57:12 ssd sshd[947]: debug1: Checking blacklist file /etc/ssh/blacklist.DSA-1024
Jan 7 13:57:12 ssd sshd[947]: debug1: private host key: #1 type 2 DSA
Jan 7 13:57:13 ssd sshd[947]: pam_env(sshd:setcred): Unable to open env file: /etc/default/locale: No such file or directory
Jan 7 13:57:13 ssd sshd[947]: pam_unix(sshd:session): session opened for user root by (uid=0)
Jan 7 13:57:13 ssd sshd[958]: pam_env(sshd:setcred): Unable to open env file: /etc/default/locale: No such file or directory
Jan 7 13:57:40 ssd sshd[947]: pam_unix(sshd:session): session closed for user root
Jan 7 13:57:40 ssd sshd[947]: pam_env(sshd:setcred): Unable to open env file: /etc/default/locale: No such file or directory

andybest

2014-01-07 14:06:30 +08:00

@juicy 我reboot了系统，dropbear 与 openssh 两个 ssh 服务（在不同端口）还是仍然没有开启

andybest

2014-01-07 14:13:51 +08:00

@juicy 现在是使用
/etc/init.d/ssh start
启动后，/var/log/auth.log中会多一条记录：

Jan 7 14:10:32 ssd dropbear[412]: premature exit: Failed to daemonize: No such device

同时SSH服务并没有启动

juicy

2014-01-07 14:21:21 +08:00

reboot之前添加完/var/run/sshd/ 之后运行 /etc/init.d/ssh start还是不能正常启动sshd?

andybest

2014-01-07 14:25:45 +08:00

@juicy 是的，使用
/usr/sbin/sshd -d
可以启动，但如果用
/etc/init.d/ssh start
则无法启动，并且 auth.log里多一条记录：
Jan 7 14:15:12 ssd dropbear[453]: premature exit: Failed to daemonize: No such device

andybest

2014-01-07 14:28:44 +08:00

@juicy 使用 /usr/sbin/sshd -d 可正常启动，输出信息为：

root@ssd:/# /usr/sbin/sshd -d
debug1: sshd version OpenSSH_5.3p1 Debian-3ubuntu7
debug1: read PEM private key done: type RSA
debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048
debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048
debug1: private host key: #0 type 1 RSA
debug1: read PEM private key done: type DSA
debug1: Checking blacklist file /usr/share/ssh/blacklist.DSA-1024
debug1: Checking blacklist file /etc/ssh/blacklist.DSA-1024
debug1: private host key: #1 type 2 DSA
debug1: rexec_argv[0]='/usr/sbin/sshd'
debug1: rexec_argv[1]='-d'
debug1: Bind to port 22 on 0.0.0.0.
Server listening on 0.0.0.0 port 22.
debug1: Bind to port 22 on ::.
Server listening on :: port 22.