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Centmin Mod Site & Data Migration

Centmin Mod users might want to eventually move web hosts or transfer their site data files and databases to a new server. The below manual guide outlines one of the many ways you can transfer data. The guide below utilises SSH key pair created via keygen.sh tool I wrote which sets up the connection between source server (where live data is) and the remote server (your new server) and then uses rsync to transfer selective server and site files. Then you'll use mysqldump to backup data and restore to remote server on the fly. This maybe slower than doing mysqldump to sql file on local server and then transferring the file to remote and then doing restore of the backup sql file. Large MySQL databases may need some tweaking for this part.

CSF Firewall Configuration

First, properly whitelist source and remote server's IP address and sshd ports in CSF Firewall.

On source data server add to /etc/csf/csf.allow the following which whitelists TCP connections to destination default sshd port 22 on remote destination server IP 111.222.333.444. Change sshd port if it is not 22 on remote destination server.

Code (Text):

tcp|out|d=22|d=111.222.333.444

then restart CSF Firewall service

Code (Text):

csf -ra

On remote destination server add to /etc/csf/csf.allow which whitelists TCP connections to destination default sshd port 22 from source data server's IP 1.2.3.4

Code (Text):

tcp|in|d=22|s=1.2.3.4

then restart CSF Firewall service

Code (Text):

csf -ra

keygen.sh passwordless setup

Second, setup keygen.sh tool on your source data server (the server which has the original data you want to transfer)

Code (Text):

mkdir -p /root/tools
cd /root/tools
git clone https://github.com/centminmod/keygen

To update keygen tool use git

Code (Text):

cd /root/tools/keygen
git stash
git pull

Then using keygen.sh tool generation your ssh key pair. You will need your remote server IP address (the IP of the server you want to transfer the source data to).

Define and set that in variable remoteip and define the default sshd port of remoteip server and a comment to describe the key. You need to type these into your SSH client session to set their values. They will only survive in the current SSH client session. If you exit it, you will need to retype these before you run the rest of the commands outlined below.

Code (Text):

remoteip=111.222.333.444
port=22
comment=mykey
remoterootpass=yourremoteserver_rootpassword

Then run keygen.sh tool

Code (Text):

cd /root/tools/keygen
./keygen.sh gen rsa $remoteip $port root $comment $remoterootpass

First time you connect you'll be asked about authenticity of the remote host ip and get a fingerprint displayed and ask if you are sure you want to continue connecting. Answer yes

Code (Text):

The authenticity of host 'remoteipaddress (remoteipaddress)' can't be established.
ECDSA key fingerprint is 68:8x:2e:6d:c0:c1:7s:81:73:c0:7a:82:45:2e:1c:98.
Are you sure you want to continue connecting (yes/no)? yes

You'll end up with private and public key files named myX where X is a number which would increment automatically if you re-run this command on same server.

• private key at /root/.ssh/my1.key
• public key at /root/.ssh/my1.key.pub

You'll now be able to ssh into remote server with just specifying the path to your private key you generated

Code (Text):

ssh root@$remoteip -p 22 -i ~/.ssh/my1.key

On your remote server at /root/.ssh you'll have an authorized_keys file now with an entry for the public key identified by the comment you setup earlier i.e. mykey. The entry is the public key contents from your file generated at /root/.ssh/my1.key.pub

Code (Text):

cat /root/.ssh/authorized_keys
ssh-rsa AAAAB3....pOlOCB/UhEQ== mykey

The keygen.sh script will also test the remote connection by connecting to it using the created SSH key pair identity and list the output for uname -a command and also give you a manual tip to setup /root/.ssh/config for an alias you can use to connect.

Example below where remote hostname ip is 111.222.333.444:

Code (Text):

-------------------------------------------------------------------
Testing connection
-------------------------------------------------------------------

ssh root@111.222.333.444 -p 22 -i /root/.ssh/my1.key "uname -a"
Linux remotehostname 2.6.32-642.13.1.el6.x86_64 #1 SMP Wed Jan 11 20:56:24 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

-------------------------------------------------------------------
Setup source server file /root/.ssh/config
-------------------------------------------------------------------

Add to /root/.ssh/config:

Host 111.222.333.444-my1
  Hostname 111.222.333.444
  Port 22
  IdentityFile /root/.ssh/my1.key
  User root

-------------------------------------------------------------------
Once /root/.ssh/config entry added, can connect via Host label:
 111.222.333.444-my1
-------------------------------------------------------------------

ssh 111.222.333.444-my1

So now instead of using command

Code (Text):

ssh root@$remoteip -p 22 -i ~/.ssh/my1.key

You can now use

Code (Text):

ssh 111.222.333.444-my1

Revoke Public Keys

After transferring and confirming all data is intact, you want to revoke the public key on the remote server to prevent the source data server from future connections to the new remote server if this is a site/data migration to a new server (remote server).

---

To revoke a public key from your remote server so that the source data server can not connect to the remote server anymore, you need to remove the generated public key from remote server's /root/.ssh/authorized_keys file. Again you use the comment i.e. mykey as a filter for sed deletion of the line.

Code (Text):

sed -i '/mykey$/d' /root/.ssh/authorized_keys 

Security

Apart from revoking the public key outlined above after successful migration, I would also recommend changing remote server's root user password afterwards. (The keygen.sh SSH key pair creation command passes the server root password on command line).

You'd also want to revoke source server's whitelisted ip on remote server's CSF config at /etc/csf/csf.allow and remove the entry you added earlier

Code (Text):

tcp|in|d=22|s=1.2.3.4

then restart CSF firewall

Code (Text):

csf -ra

 

Rsync & mysqldump transfers

Then next is using the above generated ssh key pair to rsync your site files + mysql databases over to new remote server with remoteip = 111.222.333.44 on sshd port 22

Define your remoteip, port and privatekey name i.e. my1.key. You need to type these into your SSH client session to set their values. They will only survive in the current SSH client session. If you exit it, you will need to retype these before you run the rest of the commands outlined below.

Code (Text):

remoteip=111.222.333.444
port=22
privatekey=my1.key
backupdir=/home/backupsql
DUMPOPT='-Q -K --max_allowed_packet=256M --net_buffer_length=65536 --routines --events --triggers --hex-blob'
CLIENTOPT='--max_allowed_packet=256M --net_buffer_length=65536'
mkdir -p $backupdir

rsync relevant data which assumes on remote destination server, centmin mod is installed but no vhosts or mysql databases have been created. It also assumes /root/.my.cnf is setup for mysql root user password which is automatically done on initial Centmin Mod installs

file data with rsync options -avzin where n is for dry run so no data is actually transferred. If all the dry runs look good, remove n to become -avzi for the below commands.

Notes

• I commented out the transfer of /etc/csf/csf.conf CSF Firewall config file as you may have on source server IPSET disabled but enabled on remote server, so you do not want to disable IPSET on the remote server by transferring the config file for CSF.
• Also commented out /etc/my.cnf for similar reason due to differences in preset configs between source and remote servers
• The data migration process can take a very long time for large data set sized site accounts so you will want to run the below SSH based commands in a Screen session or Tmux session which allows the session to survive SSH disconnections. If your ISP or SSH connection is disconnected, you just re-attach the Screen or Tmux session once you log back into SSH and proceed where you left off of.
• If you use 123.09beta01's Letsencrypt SSL certificates on old server and need to move them over to new server, you would need to on new server after Centmin Mod 123.09beta01 or higher install first install acme.sh
  Code (Text):

  echo "LETSENCRYPT_DETECT='y'" >> /etc/centminmod/custom_config.inc
  /usr/local/src/centminmod/addons/acmetool.sh acmeinstall
  

  
  Which will setup acme.sh auto renewal cronjob and below rsync command for /root/.acme.sh/ will cover over your existing Letsencrypt auto renewal profiles.

dry run with 'n'

Code (Text):

cd /home
rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" --exclude 'domains/*/log/*' --exclude 'domains/*/backup/*' /home/nginx/ root@$remoteip:/home/nginx
rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" --exclude 'conf.d/virtual.conf' /usr/local/nginx/conf/ root@$remoteip:/usr/local/nginx/conf
rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/centminmod/custom_config.inc root@$remoteip:/etc/centminmod/custom_config.inc
rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /usr/local/etc/php-fpm.conf root@$remoteip:/usr/local/etc/php-fpm.conf
#rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/my.cnf root@$remoteip:/etc/my.cnf
#rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/csf/csf.conf root@$remoteip:/etc/csf/csf.conf
rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/init.d/memcached root@$remoteip:/etc/init.d/memcached
rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/pure-ftpd/pureftpd.passwd root@$remoteip:/etc/pure-ftpd/pureftpd.passwd

specifically for copying over letsencrypt ssl certificates auto renewal profiles and actual ssl certificates - dry run. Make sure on new server you had already run command /usr/local/src/centminmod/addons/acmetool.sh acmeinstall before hand before running the below 3 command lines (yes only 3 lines there because of browser line wrapping).

Code (Text):

ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mkdir -p /usr/local/nginx/conf/ssl/
rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /root/.acme.sh/ root@$remoteip:/root/.acme.sh/
rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /usr/local/nginx/conf/ssl/ root@$remoteip:/usr/local/nginx/conf/ssl/

live run without 'n'

Code (Text):

cd /home
rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" --exclude 'domains/*/log/*' --exclude 'domains/*/backup/*' /home/nginx/ root@$remoteip:/home/nginx
rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" --exclude 'conf.d/virtual.conf' /usr/local/nginx/conf/ root@$remoteip:/usr/local/nginx/conf
rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/centminmod/custom_config.inc root@$remoteip:/etc/centminmod/custom_config.inc
rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /usr/local/etc/php-fpm.conf root@$remoteip:/usr/local/etc/php-fpm.conf
#rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/my.cnf root@$remoteip:/etc/my.cnf
#rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/csf/csf.conf root@$remoteip:/etc/csf/csf.conf
rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/init.d/memcached root@$remoteip:/etc/init.d/memcached
rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /etc/pure-ftpd/pureftpd.passwd root@$remoteip:/etc/pure-ftpd/pureftpd.passwd

specifically for copying over letsencrypt ssl certificates auto renewal profiles and actual ssl certificates - live run. Make sure on new server you had already run command /usr/local/src/centminmod/addons/acmetool.sh acmeinstall before hand before running the below 3 command lines (yes only 3 lines there because of browser line wrapping).

Code (Text):

ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mkdir -p /usr/local/nginx/conf/ssl/
rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /root/.acme.sh/ root@$remoteip:/root/.acme.sh/
rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" /usr/local/nginx/conf/ssl/ root@$remoteip:/usr/local/nginx/conf/ssl/

Be sure to update main hostname's nginx vhost after transfer at /usr/local/nginx/conf/conf.d/virtual.conf which may have the new old server's server_name and not new server's server_name or have other settings that differ.

To read up more on rsync usage see

• Introduction to Rsync
• How To Use Rsync to Sync Local and Remote Directories on a VPS | DigitalOcean
• Rsync (Remote Sync): 10 Practical Examples of Rsync Command in Linux
• A Practical Guide to Using rsync - Created by Pete
• The Non-Beginner’s Guide to Syncing Data with Rsync
• Everything Linux - A Tutorial on Using Rsync
• How to use rsync | University of Oxford Department of Physics

MySQL Database Backup with mysqldump

On the fly piped mysqldump data to remote will bypass saving to local sql dump file on source server. This might be useful if you don't have enough disk space on source server to save the sql backup file. But for large MySQL databases might need some tuning.
The process can take a very long time for large data set sized site accounts so you will want to run the below SSH based commands in a Screen session or Tmux session which allows the session to survive SSH disconnections. If your ISP or SSH connection is disconnected, you just re-attach the Screen or Tmux session once you log back into SSH and proceed where you left off of.

To transfer individual database name setup DBNAME variable with mysql database name, remote login to create database name and then mysqldump + pipe to remote db server the data

on the fly

Code (Text):

DBNAME='dbname'
ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysqladmin create $DBNAME
mysqldump $DUMPOPT $DBNAME | ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysql $CLIENTOPT $DBNAME

If you have non-UTF8 database character set you may need to use an additional flag
--default-character-set. Example if your MySQL database is utf8mb4 instead of utf8 character set you'd add

Code (Text):

--default-character-set=utf8mb4

on the fly with --default-character-set=utf8mb4. Change CHARSET=utf8mb4 variable to the Character your MySQL database is using

Code (Text):

DBNAME='dbname'
CHARSET=utf8mb4
ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysqladmin create $DBNAME
mysqldump --default-character-set=$CHARSET $DUMPOPT $DBNAME | ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysql --default-character-set=$CHARSET $CLIENTOPT $DBNAME

You can use below command to list each MySQL database's character set & collation

Code (Text):

mysql -e "SELECT SCHEMA_NAME 'database', default_character_set_name 'charset', DEFAULT_COLLATION_NAME 'collation' FROM information_schema.SCHEMATA;"

Example all databases below are UTF8 character & collation based.

Code (Text):

mysql -e "SELECT SCHEMA_NAME 'database', default_character_set_name 'charset', DEFAULT_COLLATION_NAME 'collation' FROM information_schema.SCHEMATA;"
+--------------------+---------+-----------------+
| database           | charset | collation       |
+--------------------+---------+-----------------+
| information_schema | utf8    | utf8_general_ci |
| mysql              | utf8    | utf8_general_ci |
| performance_schema | utf8    | utf8_general_ci |
| pgo_train          | utf8    | utf8_general_ci |
+--------------------+---------+-----------------+

list of database names, same as above just space separated list of mysql database names

on the fly

Code (Text):

DBNAME='dbname dbname2 dbname3'
for db in $DBNAME; do ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysqladmin create $db; mysqldump $DUMPOPT $db | ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysql $CLIENTOPT $db; done

on the fly with --default-character-set=utf8mb4. Change CHARSET=utf8mb4 variable to the Character your MySQL database is using

Code (Text):

DBNAME='dbname dbname2 dbname3'
CHARSET=utf8mb4
for db in $DBNAME; do ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysqladmin create $db; mysqldump --default-character-set=$CHARSET $DUMPOPT $db | ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysql --default-character-set=$CHARSET $CLIENTOPT $db; done

Or all mysql databases on server

on the fly

Code (Text):

DBNAME=$(mysql -N -e "show databases;" | grep -wEv '(information_schema|performance_schema|mysql)')
for db in $DBNAME; do ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysqladmin create $db; mysqldump $DUMPOPT $db | ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysql $CLIENTOPT $db; done

on the fly with --default-character-set=utf8mb4. Change CHARSET=utf8mb4 variable to the Character your MySQL database is using

Code (Text):

DBNAME=$(mysql -N -e "show databases;" | grep -wEv '(information_schema|performance_schema|mysql)')
CHARSET=utf8mb4
for db in $DBNAME; do ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysqladmin create $db; mysqldump --default-character-set=$CHARSET $DUMPOPT $db | ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysql --default-character-set=$CHARSET $CLIENTOPT $db; done

save to local sql backup file instead of on the fly you can do this instead for all mysql databases on server

Code (Text):

DBNAME=$(mysql -N -e "show databases;" | grep -wEv '(information_schema|performance_schema|mysql)')
for db in $DBNAME; do ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysqladmin create $db; mysqldump $DUMPOPT $db > $backupdir/$db.sql; done

save to local sql with --default-character-set=utf8mb4. Change CHARSET=utf8mb4 variable to the Character your MySQL database is using

Code (Text):

DBNAME=$(mysql -N -e "show databases;" | grep -wEv '(information_schema|performance_schema|mysql)')
CHARSET=utf8mb4
for db in $DBNAME; do ssh root@$remoteip -p $port -i ~/.ssh/$privatekey mysqladmin create $db; mysqldump --default-character-set=$CHARSET $DUMPOPT $db > $backupdir/$db.sql; done

You database backups will be saved to source server $backupdir defined above as backupdir=/home/backupsql. So /home/backupsql/dbname.sql.

Code (Text):

ls -lah /home/backupsql/
total 4.0K
drwxr-xr-x  2 root root   20 Feb  9 05:13 .
drwxr-xr-x. 6 root root   63 Feb  9 04:21 ..
-rw-r--r--  1 root root 1.4K Feb  9 05:13 db1.sql

You'll need to transfer these to remote server i.e. via rsync or scp

Code (Text):

rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" ${backupdir}/ root@$remoteip:${backupdir}/

example output from dry run

Code (Text):

rsync -avzin --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" ${backupdir}/ root@$remoteip:${backupdir}/
sending incremental file list
created directory /home/backupsql
cd+++++++++ ./
<f+++++++++ db1.sql

Number of files: 2
Number of files transferred: 1
Total file size: 1358 bytes
Total transferred file size: 1358 bytes
Literal data: 0 bytes
Matched data: 0 bytes
File list size: 33
File list generation time: 0.001 seconds
File list transfer time: 0.000 seconds
Total bytes sent: 48
Total bytes received: 18

sent 48 bytes  received 18 bytes  3.38 bytes/sec
total size is 1358  speedup is 20.58 (DRY RUN)

Then live run with 'n' flag in -avzi

Code (Text):

rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" ${backupdir}/ root@$remoteip:${backupdir}/

live run example output

Code (Text):

rsync -avzi --progress --stats -e "ssh -p $port -i $HOME/.ssh/$privatekey" ${backupdir}/ root@$remoteip:${backupdir}/
sending incremental file list
created directory /home/backupsql
cd+++++++++ ./
<f+++++++++ db1.sql
        1358 100%    0.00kB/s    0:00:00 (xfer#1, to-check=0/2)

Number of files: 2
Number of files transferred: 1
Total file size: 1358 bytes
Total transferred file size: 1358 bytes
Literal data: 1358 bytes
Matched data: 0 bytes
File list size: 33
File list generation time: 0.001 seconds
File list transfer time: 0.000 seconds
Total bytes sent: 534
Total bytes received: 34

sent 534 bytes  received 34 bytes  29.13 bytes/sec
total size is 1358  speedup is 2.39

To verify list database names on both servers via command

Code (Text):

mysql -N -e "show databases;" | grep -wEv '(information_schema|performance_schema|mysql)'

and if used saved sql files to local source server check on both servers

Code (Text):

ls -lah /home/backupsql/
total 12K
drwxr-xr-x  2 root root 4.0K Feb  9 05:13 .
drwxr-xr-x. 7 root root 4.0K Feb  9 05:20 ..
-rw-r--r--  1 root root 1.4K Feb  9 05:13 db1.sql

Restoring MySQL sql backup files

If you choose to save MySQL database backups to local sql files on source server and transferred them to remote server, you now need to restore the sql files via command below where dbname = your database name. This can take quite a while depending on database size.

Code (Text):

CLIENTOPT='--max_allowed_packet=256M --net_buffer_length=65536'
mysql $CLIENTOPT dbname < /home/backupsql/dbname.sql

Backup MySQL Grant Privileges + MySQL user/passwords

Note, this won't transfer custom created mysql usernames and passwords created on old server. You can easily backup mysql grants for this

This command outputs the list of db user grant statements which need replaying on destination mysql server (import into mysql system database)

Code (Text):

mysql --batch --skip-column-names -e "SELECT user, host FROM user" mysql | while read user host; do if [[ "$user" != 'root' ]]; then mysql --batch --skip-column-names -e "SHOW GRANTS FOR '$user'@'$host'" | sed -e 's|$|;|'; fi; done

example

Code (Text):

mysql --batch --skip-column-names -e "SELECT user, host FROM user" mysql | while read user host; do if [[ "$user" != 'root' ]]; then mysql --batch --skip-column-names -e "SHOW GRANTS FOR '$user'@'$host'" | sed -e 's|$|;|'; fi; done

GRANT USAGE ON *.* TO 'dbuser1'@'localhost' IDENTIFIED BY PASSWORD '*196BDEDE2AE4F84CA44C47D54D78478C7E2BD7B7';
GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE ON `dbname2`.* TO 'dbuser1'@'localhost';

You'll then need to replay these GRANT sql queries to the new remote server's MySQL server via mysql interactive command or via mysql on the command line.

MySQL on the command line would be via wrapping the queries in mysql -e "YOUR GRANT CMD" commands.

Code (Text):

mysql -e "YOUR GRANT CMD"

So

Code (Text):

GRANT USAGE ON *.* TO 'dbuser1'@'localhost' IDENTIFIED BY PASSWORD '*196BDEDE2AE4F84CA44C47D54D78478C7E2BD7B7';

becomes SSH command to run, it will return empty if successful

Code (Text):

mysql -e "GRANT USAGE ON *.* TO 'dbuser1'@'localhost' IDENTIFIED BY PASSWORD '*196BDEDE2AE4F84CA44C47D54D78478C7E2BD7B7';"

and

Code (Text):

GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE ON `dbname2`.* TO 'dbuser1'@'localhost';

Due to backticks having different meaning on SSH command line to mean a command, the GRANT command needs to change and remove the backticks for

Code (Text):

`dbname2`.*

to become

Code (Text):

dbname2.*

So becomes SSH command to run, it will return empty if successful

Code (Text):

mysql -e "GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE ON dbname2.* TO 'dbuser1'@'localhost';"

To verify, you can list the grant privileges for the user i.e. in this case dbuser1

Code (Text):

mysql -e "SHOW GRANTS for 'dbuser1'@'localhost'"

example output

Code (Text):

mysql -e "SHOW GRANTS for 'dbuser1'@'localhost'"
+----------------------------------------------------------------------------------------------------------------------------------------------+
| Grants for dbuser1@localhost                                                                                                                 |
+----------------------------------------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'dbuser1'@'localhost' IDENTIFIED BY PASSWORD '*196BDEDE2AE4F84CA44C47D54D78478C7E2BD7B7'                               |
| GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE ON `dbname2`.* TO 'dbuser1'@'localhost' |
+----------------------------------------------------------------------------------------------------------------------------------------------+

 

Summary

There are many ways to transfer data so the above outlined guide is not the only way to do it. The above guide is recommended to be practiced with test remote servers. I'd maybe schedule once a week or fortnight or month, you can spin up an hourly test VPS server like Linode.com, Vultr.com or DigitalOcean and test this process out. The more you practice, the more it becomes second nature

For Centmin Mod Premium Users, like dbbackup.sh, will eventually have a dedicated cm-transfer.sh tool which could automate the above to allow server data migrations. This requires a lot testing before cm-transfer.sh is available. The testing and bug report/feedback of the above manual steps will also serve as feedback for improvements to cm-transfer.sh routines.

 

Preview Centmin Mod Domain Before DNS Updates

If you want to preview migrated domains on new centminmod server without updating DNS, on Linux edit /etc/hosts or on Windows PC edit your windows HOSTS file at c:\Windows\System32\Drivers\etc\hosts (see guide at Modify your hosts file | Knowledge Center | Rackspace Hosting or install Hostman app HostsMan - abelhadigital.com which can manage the file too and allows easy dns flushing when you make changes to the hosts file.

c:\Windows\System32\Drivers\etc\hosts contents to preview without DNS update

Code:

centminmodserver-ip-address domain.com

to disable preview comment it out and flush dns for your system

Code:

#centminmodserver-ip-address domain.com

Hostsman app to flush dns and edit the c:\Windows\System32\Drivers\etc\hosts file

Update: for MacOS users there's How to edit your Mac's Hosts file and why you would want to