Connecting to a MySQL container in the same pod - php

Good day,
I am using Kubernetes to run containers on the google container engine.
The idea is to run two containers in a pod. One container uses the docker mysql image, the other runs php, laravel, nginx and composer.
Locally, this works. The idea is that the php can connect to the database on localhost, and this should work if both containers are in the same pod. However, when the pod is launched, we see the following message in the log:
SQLSTATE[HY000] [2002] Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)
The only difference is that when testing locally, I change localhost to the internal docker ip.
Thanks and good day

On Unix, MySQL programs treat the host name localhost specially, in a way that is likely different from what you expect compared to other network-based programs. For connections to localhost, MySQL programs attempt to connect to the local server by using a Unix socket file. This occurs even if a --port or -P option is given to specify a port number. To ensure that the client makes a TCP/IP connection to the local server, use --host or -h to specify a host name value of 127.0.0.1, or the IP address or name of the local server. You can also specify the connection protocol explicitly, even for localhost, by using the --protocol=TCP option. For example:
shell> mysql --host=127.0.0.1
shell> mysql --protocol=TCP
The --protocol option enables you to establish a particular type of connection even when the other options would normally default to some other protocol.
The other solution is using Kubernetes Volume abstraction to share a path between containers. Edit /etc/mysql/my.cnf on both containers' images and change socket location for both MySQL server and client to point to the shared directory or disk.

MySQL comes preconfigured to only support named pipe connections on the localhost, if you are going to connect to it from another logical machine you need to locate the following line in your my.cnf file...
#bind-address = 127.0.0.1
and replace it with...
bind-address = {your network ip here}
Once you have enabled the bind address restart your mysql server, check the error log to ensure that no exceptions occurred with binding the address, and then login as root and create a new user account attached to that ip address which you can then use to access MySQL from any other logical machine as long as you connect to it using the IP address you defined in my.cnf.
Please note by default the root account is only accessible from the localhost so you will either need to create a new user account or alter the root account to support remote connections (not secure)

Related

Docker Mysql+PHP [Port mismatch issue with terminal & PHP Application]

I have written a new docker-compose file for MySQL & PHP connection
From MySQL:
Port exposing 3315:3306
From PHP:
To access a MySQL from PHP server, I have added line docker-compose.yml links as 'mysql' service name
Port exposing 30005:80
My Folder structure & file [Image-1]
This is command, which I used to run the docker
docker-composer --build up
My running containers list [Image-2]
This is how I'm accessing in terminal [Image-3]
The Result of the PHP script is [Image-4]
My problem to this configuration is, when you noticed the index.php file from the Image-1.
i have used port as 3306 to connect a mysql, but when you refer the Image-3. To connect a mysql in terminal, i have used port as 3315
Issue on this, Why i need to use 3306 as port in PHP application to MySQL server, instead of using mysql(In docker-compose.yml file) exposed port 3315.
In terminal, i can able to access correctly, but when we go for application i have this problem.
Someone can help me to understand the port mismatch in application & terminal for a MySQL connect.
Thanks in advance
All your containers are in one isolated network. Mysql service has hostname - mysql and listens to port 3306.
The host machine listens to port 3315 and forwards packets into that network on port 3306.

WHMCS: How to create a new DB using a Hook [duplicate]

I am getting error:
"Lost connection to MySQL server at 'reading initial communication packet, system error: 0"
while I am going to connect my db.
If I am using localhost everything is working fine.
But when I am using my live IP address like below, it's getting error:
mysql_connect("202.131.xxx.106:xxxx", "xxxx", "xxxxx") or die(mysql_error());
Someone here suggests that it might be a firewall problem:
I have just had this problem and found it was my firewall. I use PCTools Firewall Plus and it wasn't allowing full access to MySQL. Once I changed that it was fine.
Could that be it?
Also, someone here suggests that it might be because the MySQL server is bound to the loop-back IP (127.0.0.1 / localhost) which effectively cuts you off from connecting from "outside".
If this is the case, you need to upload the script to the webserver (which is probably also running the MySQL server) and keep your server host as 'localhost'
Open mysql configuration file named my.cnf and try to find "bind-address", here replace the setting (127.0.0.1 OR localhost) with your live server ip (the ip you are using in mysql_connect function)
This will solve the problem definitely.
Allow remote connect to MySQL.
Edit file:
>sudo nano /etc/mysql/my.cnf
Comment line:
#bind-address = 127.0.0.1
Restart MySQL:
>sudo service mysql restart
Create user for remote connection.
>mysql -uroot -p
CREATE USER 'developer'#'localhost' IDENTIFIED BY 'dev_password';
CREATE USER 'developer'#'%' IDENTIFIED BY 'dev_password';
GRANT ALL ON *.* TO 'developer'#'localhost';
GRANT ALL ON *.* TO 'developer'#'%';
In my case I need to connect remotely from Windows to VirtualBox machine with Ubuntu. So I need to allow port 3306 in iptables:
>iptables -A INPUT -i eth0 -p tcp -m tcp --dport 3306 -j ACCEPT
Had this problem when setting up a new slave server. Found it was the slave server IP address was missing from the master server /etc/hosts.allow file. Added the IP address and it let me connect to the master server.
Note that I use hosts.allow and hosts.deny to control access.
I had this problem and it ended up being the prior sys admin changed the port MySQL was running on. MySQL Workbench was trying to connect to the default 3306 but the server was running on 20300.
The error means that it didn't receive a response from the port it expected to find the server on. The causes range from contacting the wrong machine (For one of a number of reasons) to the server not being on the expected port.
Check which port your server is bound to in /etc/mysql/my.cnf. Does that correspond to what is in your connect statement. If they match then try connecting with mysql from the server itself and from the command line of the machine where you are running the client. If it works form one place and not another then you may have a firewall / router configuration issue.
One more reason...
I ran into an Ubuntu server where everything was customized and could not connect because of that same error.
This setting was inside /etc/ssh/sshd_config
PermitTunnel no
After turning into
PermitTunnel yes
I was able to connect remotely to my MySQL DB
The problem on my case was MySQL being bind only to the lo on linux.
in order to solve the problem i have edited the my.cnf (found at /etc/mysql/my.cnf) removing the line bind-address=127.0.0.1
this allows mysql to bind to any network interface
I just set up mysql on a windows box. I got the OP's error when trying to connect with the Navicat MySql client on the same box. I had to specify 127.0.0.1 as the host, and that got it.
localhost, or the servers actual ip address both did not work.
This error occurred to me while trying to connect to the Google Cloud SQL using MySQL Workbench 6.3.
After a little research I found that my IP address has been changed by the internet provider and he was not allowed in the Cloud SQL.
I authorized it and went back to work.
I faced the same problem. I checked and tried to set AllowTcpForwarding Yes but it was missing in my sshd_config so no help.I didn't change sshd_config or my.cnf. Make sure the ssh hostname is NOT the same with the mysql hostname(use localhost).
In workbench, choose + to add new connection and set the following:
connection method: standard TCP/IP over SSH
SSH Hostname: 192.168.0.50:22 (replace remote SSH server IP and port(optional))
SSH Username: sshuser
You can set password or add at the prompt
MYSQL Hostname: localhost or 127.0.0.1
MYSQL Server port:3306
You can set password or add at the prompt
Test connection. It should be successful then hit OK.Viola!
I ran into this exact same error when connecting from MySQL workbench. Here's how I fixed it. My /etc/my.cnf configuration file had the bind-address value set to the server's IP address. This had to be done to setup replication. Anyway, I solved it by doing two things:
create a user that can be used to connect from the bind address in the my.cnf file
e.g.
CREATE USER 'username'#'bind-address' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON schemaname.* TO 'username'#'bind-address';
FLUSH PRIVILEGES;
change the MySQL hostname value in the connection details in MySQL workbench to match the bind-address
The problem for me was that DNS queries were blocked by the FW within the subnet. The solution was to disable DNS lookups within MySQL.
The problem was quite stupid for me.
I used to get the same issue on AWS EC2 Ubuntu machine (MariaDB is installed locally for the time being), so I tried to make SSH tunneling, and had the same issue. So I tried to ssh tunnel over terminal:
ssh -L13306:127.0.0.1:3306 root#ip.address -i my/private/key.pem
And it told me this:
Please login as the user "ubuntu" rather than the user "root".
I changed ssh user from root to ubuntu, just like my ssh config, and it connected just fine.
So check your SSH connecting user.
I oversaw this, so this too half an hour of my time, so I hope this will be useful for you.
For me the config file was found "/etc/mysql/mysql.conf.d/mysqld.cnf" commenting out bind address did the trick.
As we can see here:
Instead of skip-networking the default is now to listen only on
localhost which is more compatible and is not less secure.
I am trying to connect my db docker container on Ubuntu 18.04, same problem.
First check your device by run nmcli dev to check if device docker0 is connected.
If it is not connected, try to restart docker service:
sudo service docker restart
I tried make a telnet over remote server on port 3306.
The error message is clear
Host 'x.x.x.x' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'Connection closed by foreign host.
As root at server mysqladmin flush-hosts worked at all!
I had the same error when using localhost. I restarted the MySQL service and it worked fine.
in my case, I had ALL: ALL in hosts.deny. Changing this to ALL: PARANOID solved my problem when connecting over ssh
Ran into this same issue, Bind Address back and forth to no avail. Solution for me was flushing privileges.
mysql> FLUSH PRIVILEGES;
Firewalld blocks the IP address. so to give access, use these commands:
firewall-cmd --permanent --zone=trusted --add-source=YOUR_IP/32
firewall-cmd --permanent --zone=trusted --add-port=3306/tcp
firewall-cmd --reload
For me setting bind-address = 0.0.0.0 in mysql/my.cnf worked. It basically listens to all addresses (but still one port) then.
And don't forget restart your server: systemctl restart mysql
I just had the same problem, but in my case I solved it with
service mysqld start
In my case it was the university wifi blocking port 3306. I was able to connect by using a mobile hotspot.
Change to a mobile hotspot or another network, and if it works there, then you know that original network is blocking port 3306. If you get the same error on more than 1 network, then you know it's specific to your machine.
I had port 3306 in Docker container but in Dockerfile it was 33060. I edited the port in Docker container to 33060
Must have been added to the Dockerfile
ENV MYSQL_ROOT_HOST 172.17.0.1
I have done below 3 steps then working for me.
bind-address = "YOUR MACHINE IP" in my.cnf file at /etc/my.cnf
Restart service by command : service mysql restart
GRANT ALL PRIVILEGES ON yourDB.* TO 'username'#'YOUR_APPLICATION_IP' IDENTIFIED BY 'YOUR_PASSWORD' WITH GRANT OPTION;
I had the same issue installing MySQL docker image then trying to connect from WSL2 MySQL client.
As it was stated in the accepted answer that it should be a firewall issue, in my case this error was caused due to not allowing docker for windows to communicate to private network.
I changed the settings on "Firewall & network protection", "allow an app through firewall", "change settings" (need administrator rights) and allowed "Docker desktop backend" to connect to private network.
I had the same error on my Mac with a local MySQL installation. The problem was that the number files that MySQL was opening was too high for MacOS.
To see if you have the same problem you can run this command and look for File Descriptor errors:
tail -200 /usr/local/var/mysql/$(whoami).err | grep "Warning"
I added this line to my.cnf file and the problem was fixed:
table_open_cache = 200
Had the same problem, what worked for me was:
Go to Windows Firewall where you allow applications.
mysql probably won't be in the list, so you need to add it, its path is typically C:/Program Files (x86)/MySQL/bin/mysql
Mark both private and public networks, apply.
When connecting to Mysql remotely, I got the error.
I had this warning in /var/log/mysqld.log:
[Warning] IP address 'X.X.X.X' could not be resolved: Temporary failure in name resolution
I just added this line to /etc/hosts file:
X.X.X.X some_name
Problem solved! Not using skip-name-resolve caused some errors in my local app when connecting to MySQL.

PHP - Can't connect to a remote MySQL database

I have a MySQL database, hosted by me on a Windows server, and I would like to query it from a remote webserver. When I try to connect to the MySQL database using PHP (I know, I should be using mysqli):
$connection = #mysql_connect("203.0.113.0:3306", "username", "password");
With or without specifying the port, after a long time of loading, I get this error with an errorno of 2003:
Can't connect to MySQL server on '203.0.113.0' (4)
Here is what I get when I run netstat -n in command prompt on the server that is hosting the MySQL server: http://pastebin.com/pbRJNqCZ. It filled up the screen so I couldn't copy everything, but I know that everything else was (I saw a couple ports with a value of 3306, which is the MySQL port):
TCP 127.0.0.1:port 127.0.0.1:port ESTABLISHED
When I run netstat -a | find "LISTENING" I get: http://pastebin.com/Lqj2BrQK
Here's what I know so far:
It isn't an error with the MySQL server not being up, because I can connect to it locally.
It isn't an error with the webserver not being able to connect to MySQL databases, because I can connect to other databases
It isn't an authentication error (The username and password are correct, and the remote server has permission)
It isn't a port forwarding error, because the port 3306 is fowarded on both TCP & UDP.
It isn't an error with being able to connect to the machine the server is hosted on, because I can ping it fine.
The server isn't only listening on the localhost interface. skip-networking and bind-address are commented out in my my.cnf file.
How could I edit my connection code, or edit my MySQL server to fix this error?
Summarizing our discussion/chat:
Bind the network address 0.0.0.0 in my.cnf: bind-address = 0.0.0.0 and ensure skip-networking is commented out or not present.
Check netstat -a | find "LISTENING"
According to your pastebin there is a service listening on 3306. Test if the port is reachable on the NIC address from the server itself. This way an external firewall does not take effect. A simple test is to try a telnet connection to that port. More detailed information can be catched by the tool nmap. Nmap has displayed the mysql port as filtered. This adverts to a problem with a local packet filter, in this case the Windows firewall.
Ensure the Windows firewall is configured to allow public access to TCP port 3306 from all or a specific machine. Setup a rule in public profile or, if both servers are controled by the same domain controller, in domain profile. When the access from local machine is successful try the same from the remote web server.
If you fail to properly configure remote access to MySql port, consider to establish a SSH tunnel between the two machines. Once established you can access to MySql as if it were on the local machine. The port is then forwarded via the tunnel and on the database server side you can access the service on localhost loopback IP.

Cannot connect to mysql with 127.0.0.1

With the following code I can connect to mysql:
mysql_connect("localhost","username","");
But if I change localhost to 127.0.0.1 I get the following error:
Can't connect to MySQL server on '127.0.0.1' (13)
Why doesn't it work with 127.0.0.1?
localhost is special cased and uses UNIX sockets instead of TCP/IP. 127.0.0.1 doesn't get that special handling.
See the documentation:
On Unix, MySQL programs treat the host name localhost specially, in a way that is likely different from what you expect compared to other network-based programs. For connections to localhost, MySQL programs attempt to connect to the local server by using a Unix socket file. This occurs even if a --port or -P option is given to specify a port number. To ensure that the client makes a TCP/IP connection to the local server, use --host or -h to specify a host name value of 127.0.0.1, or the IP address or name of the local server. You can also specify the connection protocol explicitly, even for localhost, by using the --protocol=TCP option.
If it doesn't work when you use TCP/IP then the database probably isn't listening on the network. This is generally a good thing as it enhances security (not that listening on 127.0.0.1 exposes any problems, but listening on all interfaces gives more opportunity for attacks).
If you really want to allow connections via the network, then see skip-networking.
have you got an entry in your hosts file mapping 127.0.0.7 to localhost?
Do you have more than 1 mysql servers installed/running on your system? If so, please specify the port number of the mysql server you are trying to access like 127.0.0.1:3306,127.0.0.1:8889 etc.
If you do not know whether there are any other mysql server instances running on your system also, please specify the port.
You will be able to access it when you add the privileges for 'root'#'127.0.0.1' in the "USER_PRIVILEGES" table in the "information_schema" database
You might also try disabling SELINUX

Lost connection to MySQL server at 'reading initial communication packet', system error: 0

I am getting error:
"Lost connection to MySQL server at 'reading initial communication packet, system error: 0"
while I am going to connect my db.
If I am using localhost everything is working fine.
But when I am using my live IP address like below, it's getting error:
mysql_connect("202.131.xxx.106:xxxx", "xxxx", "xxxxx") or die(mysql_error());
Someone here suggests that it might be a firewall problem:
I have just had this problem and found it was my firewall. I use PCTools Firewall Plus and it wasn't allowing full access to MySQL. Once I changed that it was fine.
Could that be it?
Also, someone here suggests that it might be because the MySQL server is bound to the loop-back IP (127.0.0.1 / localhost) which effectively cuts you off from connecting from "outside".
If this is the case, you need to upload the script to the webserver (which is probably also running the MySQL server) and keep your server host as 'localhost'
Open mysql configuration file named my.cnf and try to find "bind-address", here replace the setting (127.0.0.1 OR localhost) with your live server ip (the ip you are using in mysql_connect function)
This will solve the problem definitely.
Allow remote connect to MySQL.
Edit file:
>sudo nano /etc/mysql/my.cnf
Comment line:
#bind-address = 127.0.0.1
Restart MySQL:
>sudo service mysql restart
Create user for remote connection.
>mysql -uroot -p
CREATE USER 'developer'#'localhost' IDENTIFIED BY 'dev_password';
CREATE USER 'developer'#'%' IDENTIFIED BY 'dev_password';
GRANT ALL ON *.* TO 'developer'#'localhost';
GRANT ALL ON *.* TO 'developer'#'%';
In my case I need to connect remotely from Windows to VirtualBox machine with Ubuntu. So I need to allow port 3306 in iptables:
>iptables -A INPUT -i eth0 -p tcp -m tcp --dport 3306 -j ACCEPT
Had this problem when setting up a new slave server. Found it was the slave server IP address was missing from the master server /etc/hosts.allow file. Added the IP address and it let me connect to the master server.
Note that I use hosts.allow and hosts.deny to control access.
I had this problem and it ended up being the prior sys admin changed the port MySQL was running on. MySQL Workbench was trying to connect to the default 3306 but the server was running on 20300.
The error means that it didn't receive a response from the port it expected to find the server on. The causes range from contacting the wrong machine (For one of a number of reasons) to the server not being on the expected port.
Check which port your server is bound to in /etc/mysql/my.cnf. Does that correspond to what is in your connect statement. If they match then try connecting with mysql from the server itself and from the command line of the machine where you are running the client. If it works form one place and not another then you may have a firewall / router configuration issue.
One more reason...
I ran into an Ubuntu server where everything was customized and could not connect because of that same error.
This setting was inside /etc/ssh/sshd_config
PermitTunnel no
After turning into
PermitTunnel yes
I was able to connect remotely to my MySQL DB
The problem on my case was MySQL being bind only to the lo on linux.
in order to solve the problem i have edited the my.cnf (found at /etc/mysql/my.cnf) removing the line bind-address=127.0.0.1
this allows mysql to bind to any network interface
I just set up mysql on a windows box. I got the OP's error when trying to connect with the Navicat MySql client on the same box. I had to specify 127.0.0.1 as the host, and that got it.
localhost, or the servers actual ip address both did not work.
This error occurred to me while trying to connect to the Google Cloud SQL using MySQL Workbench 6.3.
After a little research I found that my IP address has been changed by the internet provider and he was not allowed in the Cloud SQL.
I authorized it and went back to work.
I faced the same problem. I checked and tried to set AllowTcpForwarding Yes but it was missing in my sshd_config so no help.I didn't change sshd_config or my.cnf. Make sure the ssh hostname is NOT the same with the mysql hostname(use localhost).
In workbench, choose + to add new connection and set the following:
connection method: standard TCP/IP over SSH
SSH Hostname: 192.168.0.50:22 (replace remote SSH server IP and port(optional))
SSH Username: sshuser
You can set password or add at the prompt
MYSQL Hostname: localhost or 127.0.0.1
MYSQL Server port:3306
You can set password or add at the prompt
Test connection. It should be successful then hit OK.Viola!
I ran into this exact same error when connecting from MySQL workbench. Here's how I fixed it. My /etc/my.cnf configuration file had the bind-address value set to the server's IP address. This had to be done to setup replication. Anyway, I solved it by doing two things:
create a user that can be used to connect from the bind address in the my.cnf file
e.g.
CREATE USER 'username'#'bind-address' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON schemaname.* TO 'username'#'bind-address';
FLUSH PRIVILEGES;
change the MySQL hostname value in the connection details in MySQL workbench to match the bind-address
The problem for me was that DNS queries were blocked by the FW within the subnet. The solution was to disable DNS lookups within MySQL.
The problem was quite stupid for me.
I used to get the same issue on AWS EC2 Ubuntu machine (MariaDB is installed locally for the time being), so I tried to make SSH tunneling, and had the same issue. So I tried to ssh tunnel over terminal:
ssh -L13306:127.0.0.1:3306 root#ip.address -i my/private/key.pem
And it told me this:
Please login as the user "ubuntu" rather than the user "root".
I changed ssh user from root to ubuntu, just like my ssh config, and it connected just fine.
So check your SSH connecting user.
I oversaw this, so this too half an hour of my time, so I hope this will be useful for you.
For me the config file was found "/etc/mysql/mysql.conf.d/mysqld.cnf" commenting out bind address did the trick.
As we can see here:
Instead of skip-networking the default is now to listen only on
localhost which is more compatible and is not less secure.
I am trying to connect my db docker container on Ubuntu 18.04, same problem.
First check your device by run nmcli dev to check if device docker0 is connected.
If it is not connected, try to restart docker service:
sudo service docker restart
I tried make a telnet over remote server on port 3306.
The error message is clear
Host 'x.x.x.x' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'Connection closed by foreign host.
As root at server mysqladmin flush-hosts worked at all!
I had the same error when using localhost. I restarted the MySQL service and it worked fine.
in my case, I had ALL: ALL in hosts.deny. Changing this to ALL: PARANOID solved my problem when connecting over ssh
Ran into this same issue, Bind Address back and forth to no avail. Solution for me was flushing privileges.
mysql> FLUSH PRIVILEGES;
Firewalld blocks the IP address. so to give access, use these commands:
firewall-cmd --permanent --zone=trusted --add-source=YOUR_IP/32
firewall-cmd --permanent --zone=trusted --add-port=3306/tcp
firewall-cmd --reload
For me setting bind-address = 0.0.0.0 in mysql/my.cnf worked. It basically listens to all addresses (but still one port) then.
And don't forget restart your server: systemctl restart mysql
I just had the same problem, but in my case I solved it with
service mysqld start
In my case it was the university wifi blocking port 3306. I was able to connect by using a mobile hotspot.
Change to a mobile hotspot or another network, and if it works there, then you know that original network is blocking port 3306. If you get the same error on more than 1 network, then you know it's specific to your machine.
I had port 3306 in Docker container but in Dockerfile it was 33060. I edited the port in Docker container to 33060
Must have been added to the Dockerfile
ENV MYSQL_ROOT_HOST 172.17.0.1
I have done below 3 steps then working for me.
bind-address = "YOUR MACHINE IP" in my.cnf file at /etc/my.cnf
Restart service by command : service mysql restart
GRANT ALL PRIVILEGES ON yourDB.* TO 'username'#'YOUR_APPLICATION_IP' IDENTIFIED BY 'YOUR_PASSWORD' WITH GRANT OPTION;
I had the same issue installing MySQL docker image then trying to connect from WSL2 MySQL client.
As it was stated in the accepted answer that it should be a firewall issue, in my case this error was caused due to not allowing docker for windows to communicate to private network.
I changed the settings on "Firewall & network protection", "allow an app through firewall", "change settings" (need administrator rights) and allowed "Docker desktop backend" to connect to private network.
I had the same error on my Mac with a local MySQL installation. The problem was that the number files that MySQL was opening was too high for MacOS.
To see if you have the same problem you can run this command and look for File Descriptor errors:
tail -200 /usr/local/var/mysql/$(whoami).err | grep "Warning"
I added this line to my.cnf file and the problem was fixed:
table_open_cache = 200
Had the same problem, what worked for me was:
Go to Windows Firewall where you allow applications.
mysql probably won't be in the list, so you need to add it, its path is typically C:/Program Files (x86)/MySQL/bin/mysql
Mark both private and public networks, apply.
When connecting to Mysql remotely, I got the error.
I had this warning in /var/log/mysqld.log:
[Warning] IP address 'X.X.X.X' could not be resolved: Temporary failure in name resolution
I just added this line to /etc/hosts file:
X.X.X.X some_name
Problem solved! Not using skip-name-resolve caused some errors in my local app when connecting to MySQL.

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