mongodb 失败：error connecting to db server： no reachable servers

我在Ubuntu14安装了mongodb.04服务器

我无法通过"mongoimport"、"mongodump"、"mongostat"等连接到mongodb.它总是显示"无法访问服务器"

mongoimport --db test --collection restaurants --drop --file dataset.json
2015-08-25T13:08:29.802+0800    [........................] test.restaurants 0.0 B/11.3 MB (0.0%)
2015-08-25T13:08:30.306+0800    Failed: error connecting to db server: no reachable servers
2015-08-25T13:08:30.306+0800    imported 0 documents

不知怎么的，我能和mongo shell取得联系

mongo --port 27017
MongoDB shell version: 3.0.6
connecting to: 127.0.0.1:27017/test

首先，我怀疑它是否是由我的iptables引起的，所以我刷新所有iptables规则并为所有accept创建规则，但它仍然是一样的

 sudo iptables -S
    -P INPUT ACCEPT
    -P FORWARD ACCEPT
    -P OUTPUT ACCEPT
    -A INPUT -j ACCEPT
    -A INPUT -i lo -j ACCEPT
    -A FORWARD -j ACCEPT
    -A OUTPUT -j ACCEPT
    -A OUTPUT -o lo -j ACCEPT

我搜索了stackOverflow和google，有人告诉我

下面是我的mangodb配置，有人能帮我判断一下吗？

james@localhost:~$ cat /etc/mongod.conf 
# mongod.conf

# Where to store the data.

# Note: if you run mongodb as a non-root user (recommended) you may
# need to create and set permissions for this directory manually,
# e.g., if the parent directory isn't mutable by the mongodb user.
dbpath=/var/lib/mongodb

#where to log
logpath=/var/log/mongodb/mongod.log

logappend=true

port = 27017

# Listen to local interface only. Comment out to listen on all interfaces. 
#bind_ip = 127.0.0.1
# Disables write-ahead journaling
# nojournal = true

# Enables periodic logging of CPU utilization and I/O wait
#cpu = true

# Turn on/off security.  Off is currently the default
#noauth = true
#auth = true

# Verbose logging output.
verbose = true

# Inspect all client data for validity on receipt (useful for
# developing drivers)
#objcheck = true

# Enable db quota management
#quota = true

# Set oplogging level where n is
#   0=off (default)
#   1=W
#   2=R
#   3=both
#   7=W+some reads
#diaglog = 0

# Ignore query hints
#nohints = true

# Enable the HTTP interface (Defaults to port 28017).
#httpinterface = true

# Turns off server-side scripting.  This will result in greatly limited
# functionality
#noscripting = true

# Turns off table scans.  Any query that would do a table scan fails.
#notablescan = true

# Disable data file preallocation.
#noprealloc = true

# Specify .ns file size for new databases.
# nssize = <size>

# Replication Options

# in replicated mongo databases, specify the replica set name here
#replSet=setname
# maximum size in megabytes for replication operation log
#oplogSize=1024
# path to a key file storing authentication info for connections
# between replica set members
#keyFile=/path/to/keyfile