[SOLVED] Problem to connect to remote mysql server

francisko · Post by **francisko** » 2012/02/06 13:31:02

Hello,

I just install a new web server on a Linux CentOS 6. On my web site, i need to connect on a remote mysql database but i get an error "SQL error : Lost connection to MySQL server at 'reading initial communication packet', system error: 110".

I've tried the following things :
- connection on the remote database with command line.
- connection on the remote server with telnet on port 3306.
- I opened the 3306 port on iptables (input & output), i tried also with the iptables service stopped.
- I authorize httpd_can_network_connect in SELinux. I try also with SELinux disabled.

I've got a development server with the same site (and CentOS 6) and the connection with the remote database works fine. I don't understand why it doesn't work.

Could you help me please... :-?

Thx

pschaff · Post by **pschaff** » 2012/02/06 23:25:18

Welcome to the CentOS fora. Please see the recommended reading for new users linked in my signature.

Please [url=http://www.centos.org/modules/newbb/viewtopic.php?topic_id=28723&forum=54]provide more information about your system[/url] by running "./getinfo.sh package" and showing us the output file, as well as[code]rpm -qa mysql\*[/code]

francisko · Post by **francisko** » 2012/02/07 06:17:46

Hello Phil,

Thx for your answer. The result of ./getinfo.sh package shows that :

Information for package problems.
[code]
== BEGIN uname -rmi ==
2.6.32-71.el6.x86_64 x86_64 x86_64
== END uname -rmi ==

== BEGIN rpm -qa \*-release\* ==
centos-release-6-0.el6.centos.5.x86_64
== END rpm -qa \*-release\* ==

== BEGIN cat /etc/redhat-release ==
CentOS Linux release 6.0 (Final)
== END cat /etc/redhat-release ==

== BEGIN getenforce ==
Disabled
== END getenforce ==

== BEGIN free -m ==
total used free shared buffers cached
Mem: 2007 1924 82 0 114 915
-/+ buffers/cache: 893 1113
Swap: 4031 1 4030
== END free -m ==

== BEGIN rpm -qa yum\* rpm-\* python | sort ==
python-2.6.5-3.el6.x86_64
rpm-libs-4.8.0-12.el6.x86_64
rpm-python-4.8.0-12.el6.x86_64
yum-3.2.27-14.el6.centos.noarch
yum-metadata-parser-1.1.2-14.1.el6.x86_64
yum-plugin-fastestmirror-1.1.26-11.el6.noarch
yum-utils-1.1.26-11.el6.noarch
== END rpm -qa yum\* rpm-\* python | sort ==

== BEGIN ls /etc/yum.repos.d ==
CentOS-Base.repo
CentOS-Debuginfo.repo
CentOS-Media.repo
== END ls /etc/yum.repos.d ==

== BEGIN cat /etc/yum.conf ==
[main]
cachedir=/var/cache/yum/$basearch/$releasever
keepcache=0
debuglevel=2
logfile=/var/log/yum.log
exactarch=1
obsoletes=1
gpgcheck=1
plugins=1
installonly_limit=5
bugtracker_url=http://bugs.centos.org/set_project.php?project_id=16&ref=http://bugs.centos.org/bug_report_page.php?category=yum
distroverpkg=centos-release

# This is the default, if you make this bigger yum won't see if the metadata
# is newer on the remote and so you'll "gain" the bandwidth of not having to
# download the new metadata and "pay" for it by yum not having correct
# information.
# It is esp. important, to have correct metadata, for distributions like
# Fedora which don't keep old packages around. If you don't like this checking
# interupting your command line usage, it's much better to have something
# manually check the metadata once an hour (yum-updatesd will do this).
# metadata_expire=90m

# PUT YOUR REPOS HERE OR IN separate files named file.repo
# in /etc/yum.repos.d
== END cat /etc/yum.conf ==

== BEGIN yum repolist all ==
Loaded plugins: fastestmirror, refresh-packagekit
Loading mirror speeds from cached hostfile
* base: mirror.ovh.net
* extras: mirror.ovh.net
* updates: mirror.ovh.net
repo id repo name status
base CentOS-6 - Base enabled: 6,294
c6-media CentOS-6 - Media disabled
centosplus CentOS-6 - Plus disabled
contrib CentOS-6 - Contrib disabled
debug CentOS-6 - Debuginfo disabled
extras CentOS-6 - Extras enabled: 4
updates CentOS-6 - Updates enabled: 326
repolist: 6,624
== END yum repolist all ==

== BEGIN egrep 'include|exclude' /etc/yum.repos.d/*.repo ==
== END egrep 'include|exclude' /etc/yum.repos.d/*.repo ==

== BEGIN sed -n -e "/^\[/h; /priority *=/{ G; s/\n/ /; s/ity=/ity = /; p }" /etc/yum.repos.d/*.repo | sort -k3n ==
== END sed -n -e "/^\[/h; /priority *=/{ G; s/\n/ /; s/ity=/ity = /; p }" /etc/yum.repos.d/*.repo | sort -k3n ==

== BEGIN rpm -qa kernel\* | sort ==
kernel-2.6.32-71.el6.x86_64
kernel-firmware-2.6.32-71.el6.noarch
== END rpm -qa kernel\* | sort ==

The MySql packages installed on my system are :

mysql-server-5.1.47-4.el6.x86_64
mysql-libs-5.1.47-4.el6.x86_64
mysql-5.1.47-4.el6.x86_64
mysql-connector-odbc-5.1.5r1144-7.el6.x86_64

_________________
Francisko

Post by **TrevorH** » 2012/02/07 07:43:18

You're still running CentOS 6.0 and 6.2 has been out for over a month so it's probably worth updating as one of the first things you do.

At a guess it may also be worth running

[code]
setsebool -P httpd_can_network_connect_db 1
[/code]

francisko · Post by **francisko** » 2012/02/07 08:21:34

Hello Trevor,

I tried on another virtual machine with CentOS 6.2 installed and the problem is similar.

I modify SELinux to set httpd_can_network_db = 1, but that dont change anything.

I tried also to disable SELinux and IPTables but i got the same error.

francisko · Post by **francisko** » 2012/02/07 13:58:37

Hey,

The problem was not my system but the firewall on the remote server... My developpement server was authorized but not the production server.

Thanks for your help.

pschaff · Post by **pschaff** » 2012/02/07 18:51:23

Thanks for reporting back. Marking this thread [SOLVED] for posterity.

CentOS