主页 / server / 问题 / 679673
Accepted
zensys
Asked: 2015-04-01 12:59:42 +0800 CST

telnet 无法连接到没有防火墙的端口

  • 772

如果我尝试连接到 MySQL

telnet myhost.com 3306

network not reachable即使刷新所有iptables规则，我也会收到错误消息。我可以到达其他端口，例如ssh（使用与 for 相同的iptables规则ssh）。

下面是我在netstat. 它给我的印象是访问端口比访问端口更多iptables：像 10025 这样的端口在我的iptables.

我看到 MySQL 对 tcp 开放，但对 tcp6 不开放（ssh 对两者都开放）。

从 Ubuntu 服务器 12.04 升级到 14.04 后，此问题开始出现。有人对连接超时有任何建议吗？

$ netstat -tlp 3306
(No info could be read for "-p": geteuid()=1000 but you should be root.)
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 *:pop3s                 *:*                     LISTEN      -               
tcp        0      0 localhost:10023         *:*                     LISTEN      -               
tcp        0      0 localhost:10024         *:*                     LISTEN      -               
tcp        0      0 localhost:10025         *:*                     LISTEN      -               
tcp        0      0 *:mysql                 *:*                     LISTEN      -               
tcp        0      0 *:pop3                  *:*                     LISTEN      -               
tcp        0      0 localhost:spamd         *:*                     LISTEN      -               
tcp        0      0 *:imap2                 *:*                     LISTEN      -               
tcp        0      0 *:urd                   *:*                     LISTEN      -               
tcp        0      0 *:smtp                  *:*                     LISTEN      -               
tcp        0      0 *:sieve                 *:*                     LISTEN      -               
tcp        0      0 *:ssh                  *:*                     LISTEN      -               
tcp        0      0 *:imaps                 *:*                     LISTEN      -               
tcp6       0      0 [::]:pop3s              [::]:*                  LISTEN      -               
tcp6       0      0 localhost:10023         [::]:*                  LISTEN      -               
tcp6       0      0 [::]:pop3               [::]:*                  LISTEN      -               
tcp6       0      0 localhost:spamd         [::]:*                  LISTEN      -               
tcp6       0      0 [::]:imap2              [::]:*                  LISTEN      -               
tcp6       0      0 [::]:http               [::]:*                  LISTEN      -               
tcp6       0      0 [::]:urd                [::]:*                  LISTEN      -               
tcp6       0      0 [::]:smtp               [::]:*                  LISTEN      -               
tcp6       0      0 [::]:https              [::]:*                  LISTEN      -               
tcp6       0      0 [::]:sieve              [::]:*                  LISTEN      -               
tcp6       0      0 [::]:ssh               [::]:*                  LISTEN      -               
tcp6       0      0 [::]:imaps              [::]:*                  LISTEN      -   

150407 12:31:07 [Note] /usr/sbin/mysqld: Normal shutdown

150407 12:31:07 [Note] Event Scheduler: Purging the queue. 0 events
150407 12:31:07  InnoDB: Starting shutdown...
150407 12:31:10  InnoDB: Shutdown completed; log sequence number 574674933
150407 12:31:10 [Note] /usr/sbin/mysqld: Shutdown complete

150407 12:31:11 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
150407 12:31:11 [Warning] Using unique option prefix key_buffer instead of key_buffer_size is deprecated and will be removed in a future release. Please use the full name instead.
150407 12:31:12 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
150407 12:31:12 [Note] Plugin 'FEDERATED' is disabled.
150407 12:31:12 InnoDB: The InnoDB memory heap is disabled
150407 12:31:12 InnoDB: Mutexes and rw_locks use GCC atomic builtins
150407 12:31:12 InnoDB: Compressed tables use zlib 1.2.8
150407 12:31:12 InnoDB: Using Linux native AIO
150407 12:31:12 InnoDB: Initializing buffer pool, size = 128.0M
150407 12:31:12 InnoDB: Completed initialization of buffer pool
150407 12:31:12 InnoDB: highest supported file format is Barracuda.
150407 12:31:12 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
150407 12:31:12 [Note] Plugin 'FEDERATED' is disabled.
150407 12:31:12 InnoDB: The InnoDB memory heap is disabled
150407 12:31:12 InnoDB: Mutexes and rw_locks use GCC atomic builtins
150407 12:31:12 InnoDB: Compressed tables use zlib 1.2.8
150407 12:31:12 InnoDB: Using Linux native AIO
150407 12:31:12 InnoDB: Initializing buffer pool, size = 128.0M
150407 12:31:12 InnoDB: Completed initialization of buffer pool
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
150407 12:31:12  InnoDB: Retrying to lock the first data file
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
150407 12:31:13  InnoDB: Waiting for the background threads to start
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
150407 12:31:14 InnoDB: 5.5.41 started; log sequence number 574674933
150407 12:31:14 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
150407 12:31:14 [Note]   - '0.0.0.0' resolves to '0.0.0.0';
150407 12:31:14 [Note] Server socket created on IP: '0.0.0.0'.
150407 12:31:15 [Note] Event Scheduler: Loaded 0 events
150407 12:31:15 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.5.41-0ubuntu0.14.04.1'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  (Ubuntu)
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
...
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
150407 12:32:52  InnoDB: Unable to open the first data file
InnoDB: Error in opening ./ibdata1
150407 12:32:52  InnoDB: Operating system error number 11 in a file operation.
InnoDB: Error number 11 means 'Resource temporarily unavailable'.
InnoDB: Some operating system error numbers are described at
InnoDB: http://dev.mysql.com/doc/refman/5.5/en/operating-system-error-codes.html
150407 12:32:52 InnoDB: Could not open or create data files.
150407 12:32:52 InnoDB: If you tried to add new data files, and it failed here,
150407 12:32:52 InnoDB: you should now edit innodb_data_file_path in my.cnf back
150407 12:32:52 InnoDB: to what it was, and remove the new ibdata files InnoDB created
150407 12:32:52 InnoDB: in this failed attempt. InnoDB only wrote those files full of
150407 12:32:52 InnoDB: zeros, but did not yet use them in any way. But be careful: do not
150407 12:32:52 InnoDB: remove old data files which contain your precious data!
150407 12:32:52 [ERROR] Plugin 'InnoDB' init function returned error.
150407 12:32:52 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
150407 12:32:52 [ERROR] Unknown/unsupported storage engine: InnoDB
150407 12:32:52 [ERROR] Aborting

150407 12:32:52 [Note] /usr/sbin/mysqld: Shutdown complete

150407 12:32:52 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
150407 12:32:52 [Note] Plugin 'FEDERATED' is disabled.
......

将绑定地址更改为 0.0.0.0 后 netstat 的输出：

tcp        0      0 0.0.0.0:3306            0.0.0.0:*               LISTEN      18890/mysqld

输出挖掘：

; <<>> DiG 9.9.5-3ubuntu0.2-Ubuntu <<>> myhost.com ip r get 123.45.67.890 telnet 123.45.67.890 3306
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55636
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4000
;; QUESTION SECTION:
;myhost.com.        IN  A

;; ANSWER SECTION:
myhost.com. 3600    IN  A   123.45.67.890

;; Query time: 856 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Tue Apr 07 22:55:03 CEST 2015
;; MSG SIZE  rcvd: 60

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 35733
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4000
;; QUESTION SECTION:
;ip.                IN  A

;; AUTHORITY SECTION:
.           528 IN  SOA a.root-servers.net. nstld.verisign-grs.com. 2015040701 1800 900 604800 86400

;; Query time: 159 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Tue Apr 07 22:55:03 CEST 2015
;; MSG SIZE  rcvd: 106

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 17760
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4000
;; QUESTION SECTION:
;r.             IN  A

;; AUTHORITY SECTION:
.           528 IN  SOA a.root-servers.net. nstld.verisign-grs.com. 2015040701 1800 900 604800 86400

;; Query time: 55 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Tue Apr 07 22:55:03 CEST 2015
;; MSG SIZE  rcvd: 105

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 20236
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4000
;; QUESTION SECTION:
;get.               IN  A

;; AUTHORITY SECTION:
.           527 IN  SOA a.root-servers.net. nstld.verisign-grs.com. 2015040701 1800 900 604800 86400

;; Query time: 62 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Tue Apr 07 22:55:04 CEST 2015
;; MSG SIZE  rcvd: 107

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29568
;; flags: qr aa rd ra ad; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;123.45.67.890.         IN  A

;; ANSWER SECTION:
123.45.67.890.      0   IN  A   123.45.67.890

;; Query time: 0 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)

/etc/mysql/my.cnf：

#
# The MySQL database server configuration file.
#
# You can copy this to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
# 
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

# This will be passed to all mysql clients
# It has been reported that passwords should be enclosed with ticks/quotes
# escpecially if they contain "#" chars...
# Remember to edit /etc/mysql/debian.cnf when changing the socket location.
[client]
port        = 3306
socket      = /var/run/mysqld/mysqld.sock

# Here is entries for some specific programs
# The following values assume you have at least 32M ram

# This was formally known as [safe_mysqld]. Both versions are currently parsed.
[mysqld_safe]
socket      = /var/run/mysqld/mysqld.sock
nice        = 0

[mysqld]
#
# * Basic Settings
#
user        = mysql
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
port        = 3306
basedir     = /usr
datadir     = /var/lib/mysql
tmpdir      = /tmp
lc-messages-dir = /usr/share/mysql
#skip-external-locking
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
#bind-address       = 127.0.0.1
bind-address        = 0.0.0.0

#
# * Fine Tuning
#
key_buffer      = 16M
max_allowed_packet  = 16M
thread_stack        = 192K
thread_cache_size       = 8
# This replaces the startup script and checks MyISAM tables if needed
# the first time they are touched
myisam-recover         = BACKUP
#max_connections        = 100
#table_cache            = 64
#thread_concurrency     = 10
#
# * Query Cache Configuration
#
query_cache_limit   = 1M
query_cache_size        = 16M
#
# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
# As of 5.1 you can enable the log at runtime!
#general_log_file        = /var/log/mysql/mysql.log
#general_log             = 1
#
# Error log - should be very few entries.
#
log_error = /var/log/mysql/error.log
#
# Here you can see queries with especially long duration
#log_slow_queries   = /var/log/mysql/mysql-slow.log
#long_query_time = 2
#log-queries-not-using-indexes
#
# The following can be used as easy to replay backup logs or for replication.
# note: if you are setting up a replication slave, see README.Debian about
#       other settings you may need to change.
#server-id      = 1
#log_bin            = /var/log/mysql/mysql-bin.log
expire_logs_days    = 10
max_binlog_size         = 100M
#binlog_do_db       = include_database_name
#binlog_ignore_db   = include_database_name
#
# * InnoDB
#
# InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/.
# Read the manual for more InnoDB related options. There are many!
#
# * Security Features
#
# Read the manual, too, if you want chroot!
# chroot = /var/lib/mysql/
#
# For generating SSL certificates I recommend the OpenSSL GUI "tinyca".
#
# ssl-ca=/etc/mysql/cacert.pem
# ssl-cert=/etc/mysql/server-cert.pem
# ssl-key=/etc/mysql/server-key.pem



[mysqldump]
quick
quote-names
max_allowed_packet  = 16M

[mysql]
#no-auto-rehash # faster start of mysql but no tab completition

[isamchk]
key_buffer      = 16M

#
# * IMPORTANT: Additional settings that can override those from this file!
#   The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/

跟踪路由：

 1  192.168.1.1 (192.168.1.1)  4.728 ms  4.720 ms  4.707 ms
 2  1.16.15.37.dynamic.jazztel.es (37.15.16.1)  26.522 ms  26.529 ms  28.352 ms
 3  10.255.160.254 (10.255.160.254)  30.024 ms  30.017 ms  29.987 ms
 4  41.217.106.212.static.jazztel.es (212.106.217.41)  44.086 ms 45.217.106.212.static.jazztel.es (212.106.217.45)  52.257 ms 41.217.106.212.static.jazztel.es (212.106.217.41)  42.428 ms
 5  * 42.217.106.212.static.jazztel.es (212.106.217.42)  47.672 ms  52.229 ms
 6  129.216.106.212.static.jazztel.es (212.106.216.129)  57.838 ms  61.308 ms *
 7  142.216.106.212.static.jazztel.es (212.106.216.142)  89.549 ms  106.063 ms *
 8  142.216.106.212.static.jazztel.es (212.106.216.142)  76.570 ms 195.66.225.53 (195.66.225.53)  87.575 ms 142.216.106.212.static.jazztel.es (212.106.216.142)  84.337 ms
 9  195.66.225.53 (195.66.225.53)  106.011 ms  76.555 ms  105.993 ms
10  openpeering.pcextreme.nl (82.150.154.35)  84.274 ms telecity2.openpeering.nl (82.150.154.26)  87.533 ms nikhef.openpeering.nl (82.150.154.25)  105.973 ms
11  openpeering.pcextreme.nl (82.150.154.35)  87.506 ms  87.474 ms 185.27.173.130 (185.27.173.130)  79.570 ms
12  185.27.173.150 (185.27.173.150)  95.558 ms  95.510 ms 185.27.173.130 (185.27.173.130)  81.846 ms
13  185.27.173.150 (185.27.173.150)  68.465 ms *  84.567 ms
14  * * *
15  * * *
16  * * *
17  * * *
18  * * *
19  * * *
20  * * *
21  * * *
22  * * *
23  * * *
24  * * *
25  * * *
26  * * *
27  * * *
28  * * *
29  * * *
30  * * *
networking

4 个回答

  1. Best Answer

    我将如何使用普通 telnet 到某个端口来处理无法访问的网络？

    在客户端

    1. 名称解析（您实际连接到什么？）

      nslookup myhost.com

    结果是什么？什么IP？IPv4 还是 IPv6？（这将有助于不混淆输出。）

    1. 网络路径（是否有东西阻塞了通往服务器的路？）

    哦，顺便说一句，您尝试使用的操作系统是什么？如果是 Linux：

    traceroute myhost.com

    在服务器上

    1. 服务是否在监听（如果没有监听，则无法连接）

      netstat -tulpn | grep mysql

    2. 在服务器上尝试本地连接

      telnet localhost 3306

    结果是什么？

    1. 在从客户端启动 telnet 期间

      tshark -ta -n port 3306

    您是否看到来自客户端的数据包？（确保 tshark 在正确的界面上运行，如果有很多）

    如果没有数据包：网络上的某些东西阻止了它们（不是服务器上潜在的 iptables 防火墙，我们将在接下来讨论。）

    如果确实看到了数据包：没有网络问题，检查 iptables

    iptables -vnL

    它说什么？iptables -t raw -vnL, iptables -t mangle -vnL,呢iptables -t nat -vnL？

    Selinux 活跃吗？还是其他一些主机保护？

    我在关机期间看到锁定错误。您是否可能错误地运行了多个 mysqld？说什么ps -ef | grep mysql？启动和关机一样混乱吗？

    请回复详细结果。

    • 2

  2. 这一直是我之前的一个问题，我无法通过互联网连接到远程 MySQL 服务器。我做了一些快速的故障排除测试，例如：

    • 确保 mysqld 处于活动状态/已启动。
    • 确保 SELinux 已禁用，以便可以生成端口

    根据您提供的信息，您似乎已经完成了上述操作，因为我可以看到它已通过以下行绑定到 tcp：

    tcp        0      0 *:mysql                 *:*                     LISTEN      -

    然后我想起了我从 apesa 读到的一篇关于 Stackoverflow 的文章，其中包括：

    要将 MySQL 暴露给 localhost 以外的任何内容，您必须在 /etc/mysql/my.cnf 中取消注释以下行并分配给您的计算机 IP 地址而不是环回

    #Replace xxx with your IP Address 
bind-address        = xxx.xxx.xxx.xxx

    或者bind-address = 0.0.0.0如果您不想指定 IP，请添加

    然后使用新的 my.cnf 条目停止并重新启动 MySQL。运行后转到终端并输入以下命令。

    lsof -i -P | grep :3306

    这应该会在您的 xxx 中返回类似这样的实际 IP

    mysqld  1046  mysql  10u  IPv4  5203  0t0  TCP  xxx.xxx.xxx.xxx:3306 (LISTEN)

    如果上述语句正确返回，您将能够接受远程用户。但是，要让远程用户以正确的权限连接，您需要在 localhost 和 '%' 中创建该用户。

    CREATE USER 'myuser'@'localhost' IDENTIFIED BY 'mypass';
CREATE USER 'myuser'@'%' IDENTIFIED BY 'mypass';

    然后

    GRANT ALL ON *.* TO 'myuser'@'localhost';
GRANT ALL ON *.* TO 'myuser'@'%';

    如果您没有像上面那样创建相同的用户，当您在本地登录时，您可能会继承基本 localhost 权限并遇到访问问题。如果您想限制 myuser 的访问权限，则需要在此处阅读 GRANT 语句语法。

    注意：如果 lsof 没有返回或找不到，您可以根据您的 Linux 发行版在此处安装它。您不需要 lsof 来使事情正常工作，但是当事情没有按预期工作时，它非常方便。

    -> Apesa 回答：远程连接 MySQL Ubuntu

    通常这解决了我的问题，因为我没有配置 my.cnf

    • 1

  3. 如果 /etc/mysql/my.cnf 中的 bind-address 设置为 127.0.0.1，请尝试将其更改为以下内容，这将允许 MySQL 绑定到所有可用接口：

    绑定地址 = 0.0.0.0

    另外，尝试在 MySQL 本身中授予自己网络访问权限：

    mysql> 全部授予。to your-user-name@'your-hostname' IDENTIFIED BY 'your-password';

    • 0

  4. tcpwrapers: /etc/hosts.{allow,deny} 文件呢？查看您的 netstat 输出，看起来 MySQL 正在侦听所有 IPv4 地址，并且您的 iptables 也已打开。所以它归结为 IPv6 问题或 tcpwrappers，因为它们位于事物的中间并且不容易调试。

    • 0

相关问题