Mongo 重启错误 varrunmongodbmongod.pid 存在

我刚刚启动了一个新的AWS Linux AMI 2016.09.1(HVM)，并下载了最新的Mongodb版本.我使用的是MongoDB版本3.0.14.我更新了/etc/mongod.请注意:，

# mongod.conf

# for documentation of all options, see:
#   http://docs.mongodb.org/manual/reference/configuration-options/

# where to write logging data.
systemLog:
destination: file
logAppend: true
path: /var/log/mongodb/mongod.log

# Where and how to store data.
storage:
dbPath: /var/lib/mongo
journal:
enabled: true
#  engine:
#  mmapv1:
#  wiredTiger:

# how the process runs
processManagement:
  fork: true  # fork and run in background
  pidFilePath: /var/run/mongodb/mongod.pid  # location of pidfile

# network interfaces
net:
  port: 27017
#  bindIp: 127.0.0.1  # Listen to local interface only, comment to listen on
    all interfaces.


#security:

#operationProfiling:

#replication:

#sharding:

## Enterprise-Only Options

#auditLog:

#snmp:

我第一次使用服务运行Mongodb，

sudo service mongod start

一切正常.当我停止Mongodb并重新启动时，

sudo service mongod stop
sudo service mongod restart

我得到以下错误，

Error starting mongod. /var/run/mongodb/mongod.pid exists.

下面是日志(log)文件/var/log/mongodb/mongod中的内容.日志(log)

2017-01-16T14:11:16.869+0000 I CONTROL  ***** SERVER RESTARTED *****
2017-01-16T14:11:16.872+0000 I CONTROL  [initandlisten] MongoDB starting :
    pid=2820 port=27017 dbpath=/var/lib/mongo 64-bit hos
    t=ip-10-0-0-91
2017-01-16T14:11:16.872+0000 I CONTROL  [initandlisten] db version v3.0.14
2017-01-16T14:11:16.872+0000 I CONTROL  [initandlisten] git version:
    08352afcca24bfc145240a0fac9d28b978ab77f3
2017-01-16T14:11:16.872+0000 I CONTROL  [initandlisten] build info: Linux
    ip-10-63-190-181 3.4.43-43.43.amzn1.x86_64 #1 SMP Mon
    May 6 18:04:41 UTC 2013 x86_64 BOOST_LIB_VERSION=1_49
2017-01-16T14:11:16.872+0000 I CONTROL  [initandlisten] allocator: tcmalloc
2017-01-16T14:11:16.872+0000 I CONTROL  [initandlisten] options: { config:
    "/etc/mongod.conf", net: { port: 27017 }, processMan
    agement: { fork: true, pidFilePath: "/var/run/mongodb/mongod.pid" },
    storage: { dbPath: "/var/lib/mongo", journal: { enabled: t
    rue } }, systemLog: { destination: "file", logAppend: true, path:   
    "/var/log/mongodb/mongod.log" } }
2017-01-16T14:11:16.893+0000 E NETWORK  [initandlisten] Failed to unlink
    socket file /tmp/mongodb-27017.sock errno:1 Operation
    not permitted
2017-01-16T14:11:16.893+0000 I -        [initandlisten] Fatal Assertion   
    28578
2017-01-16T14:11:16.893+0000 I -        [initandlisten]

***aborting after fassert() failure

我看过好几篇关于这个问题的博客，都有解决方案，但似乎都不管用.周日花了一整天的时间想弄明白这一点.在运行早期的AWS实例和Mongo之前，从未出现过这个问题.