Cloud Applications - Cloud Services Store

Most frequently asked questions

How to connect to MySQL (Web interface & CLI)
Web Interface

Adminer is a database management web applicarion

URL : https://12.34.56.789:12322
Username: adminer
Password :

Command line

MySQL command line tool log in as root (no password required):
```
$ mysql --user root 
Welcome to the MySQL monitor. Commands end with ; or \g. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. 
mysql>
```
How to connect to Cloud Application shell (Web interface & CLI)
Web based command line

URL : https://12.34.56.789:12320/
User : root

SSH

Login as root.

From Windows you can access your server using a free simple SSH client program called Putty located at our Downloads.

From Linux :

ssh root@12.34.56.789

* Replace 12.34.56.789 with a valid IP or hostname.
Hot to connect to System control panel (Webmin)
System control panel

Point your browser to: https://12.34.56.789:12321/

Username : root
Password :

* Replace 12.34.56.789 with a valid IP or hostname.
What is Reverse DNS?
Reverse DNS (rDNS) is name resolution that looks up an IP addresses to obtain a domain name, performing the opposite function of the DNS server, which turns domain names into IP addresses.

Reverse DNS can be used as a spam filter. Typically, spammers use invalid IP addresses, that is, ones that do not match domain names. A reverse DNS program looks up the IP address of an incoming message and, if no valid domain name is found, the server blocks the message. Although reverse DNS is fairly effective for filtering spam, it also often blocks valid emails.

Our administrators configure reverse DNS on all of our email servers. If you administrate your own server, you can contact your IP address's provider to configure reverse DNS.
Tune MySQL / mariadb database for WooCommerce and WordPress
WooCommerce can really give mysql or mariadb a pounding.

On smaller hosting platforms WooCommerce will grind to a halt.

If you have a VPS, here are a few things you can tune, to give you fast database performance. The faster the database goes, the faster WooCommerce goes:

InnoDb cache

Assuming of course that you’re using innodb (which is a must – see below)

innodb_buffer_pool_size=1024M

The size should be as large as your wp_postmeta and wp_options tables, or 50% or more of your WooCommerce database. Don’t go above 25% of the RAM in your VPS.

Query Cache

There are a few articles out there saying disable query cache , but I think it really helps the WordPress wp_options table, which WooCommerce stores most of its data in.

query_cache_limit=2M

query_cache_size=64M

query_cache_type=1

If you have a lot more memory in your VPS, try this:

query_cache_limit=8M

query_cache_size=256M

query_cache_type=1

Make sure you’re using innodb

Innodb is the fastest and most reliable database engine for mysql , mariadb, WordPress and WooCommerce. Here’s how to check.
- Login to PHPMyAdmin
- Select the database for your WP site.
- Click the SQL tab.
- Type this: show table status
- Click GO.
You are looking for engine and you want InnoDB.

If it’s myisam you need to fix it. Use this command in PHPMyAdmin (as above). make sure you have a good backup first.
- ALTER TABLE tablename ENGINE = InnoDB
- you’ll need to it for each table that was myisam (replace tablename with each table)
Resize an LVM volume
Logical Volume Management (AKA LVM) is a powerful, robust mechanism for managing storage space.

In TurnKey 11, instead of installing the root filesystem directly to a fixed size partition, we setup LVM by default, and install the root filesystem to a Logical Volume, which may later be expanded, even across multiple physical devices.

Unfortunately, as with anything powerful, to get the most out of LVM you first have to negotiate a learning curve. From the feedback we've been getting it seems that confusion regarding LVM is common with new users, so here's a quick "crash course"...

How LVM works

In LVM, there are several layers, each builds on top of the other:

PV[s] (Physical Volumes) -> VG[s] (Volume Groups) -> LV[s] (Logical Volumes) -> Filesystems.

Logical Volumes are allocated/extended within the boundaries of their underlying storage pool which is called a Volume Group in LVM terminology.

For example, in TurnKey the filesystem is installed by default to the /dev/turnkey/root Logical Volume, which is allocated within the turnkey Volume Group:
```
--- Logical volume ---

  LV Name                /dev/turnkey/root

  VG Name                turnkey

  LV UUID                OzX3fe-aRQa-81XM-0vCV-8aJo-eUL4-6J90XJ

  LV Write Access        read/write

  LV Status              available

  # open                 1

  LV Size                17.0 GiB

  Current LE             4502

  Segments               2

  Allocation             inherit

  Read ahead sectors     auto

  - currently set to     256

  Block device           251:0
```
Out of the box the turnkey Volume Group doesn't have too much free space:
```
# vgdisplay

  --- Volume group ---

  VG Name               turnkey

  System ID

  Format                lvm2

  Metadata Areas        1

  Metadata Sequence No  3

  VG Access             read/write

  VG Status             resizable

  MAX LV                0

  Cur LV                2

  Open LV               2

  Max PV                0

  Cur PV                1

  Act PV                1

  VG Size               18.14 GiB

  PE Size               4.00 MiB

  Total PE              4645

  Alloc PE / Size       4480 / 17.50 GiB

  Free  PE / Size       165 / 660.00 MiB

  VG UUID               IwaFL0-QCi8-iIUE-TWjQ-R906-PYpH-gMPaH9
```
We can only extend a Logical Volume within the free space of the underlying Volume Group. How much free space we currently have within the Volume Group can be seen in this part of the output:
```
Free  PE / Size       165 / 660.00 MiB
```
In the above example we only have 660 MB to allocate to LVMs within the turnkey Volume Group. So if we want to extend the root LV we'll have to first extend the VG backs it up.

Volume Groups group together Physical Volumes. That's why they're called Volume Groups. This command will show us which Physical Volumes have been registered into LVM, and to which volume groups they have been assigned:
```
# pvdisplay

  --- Physical volume ---

  PV Name               /dev/sda2

  VG Name               turnkey

  PV Size               18.15 GiB / not usable 4.00 MiB

  Allocatable           yes

  PE Size               4.00 MiB

  Total PE              4645

  Free PE               165

  Allocated PE          4480

  PV UUID               H1Prpv-0VXR-7moE-zsbt-eyVt-m0fQ-GkAT6w
```
In this example we only have one Physical Volume (the /dev/sda2 partition) in the turnkey Volume Group.

Extending a Logical Volume

Bottom line: if the underlying Volume Group doesn't have enough free space, to extend the Logical Volume you'll first have to extend the underlying Volume Group by adding another Physical Volume to it.

In VMWare you could either create a new virtual hard disk device to add to the volume group, or extend an existing virtual hard disk device, create a new partition with cfdisk, and add the new partition to the Volume Group:
```
# example #1: you've added to VMWare a new virtual hard disk called /dev/sdb

pvcreate /dev/sdb

vgextend turnkey /dev/sdb



# example #2: you've expanded the existing sda hard disk

cfdisk /dev/sda  # creating /dev/sda3 (you may need to reboot before you can see this)

pvcreate /dev/sda3

vgextend turnkey /dev/sda3
```
After you've extended the Volume Group, you are free to extend the underlying Logical Volume:
```
# lvextend -L+10G /dev/turnkey/root

Extending logical volume root to 27.0 GiB

Logical volume root successfully resized
```
Finally, you'll have to resize the filesystem within /dev/turnkey/root so it can see that the underlying block device just got 10G bigger:
```
# resize2fs /dev/turnkey/root

resize2fs 1.41.11 (14-Mar-2010)

Filesystem at /dev/turnkey/root is mounted on /; on-line resizing required

old desc_blocks = 2, new_desc_blocks = 2

Performing an on-line resize of /dev/turnkey/root to  7077888 (4k) blocks.

The filesystem on /dev/turnkey/root is now 7077888 blocks long.
```

How to extend an EXT4 partition using parted and resize2fs

Firstly, we want to extend the partition using parted:

Bash:

root@cana:~# parted /dev/sda

GNU Parted 3.2

Using /dev/sda

Welcome to GNU Parted! Type 'help' to view a list of commands.

(parted) resizepart 1                                                  

Warning: Partition /dev/sda1 is being used. Are you sure you want to continue?

Yes/No? Yes                                                            

End?  [275GB]? -0                                                      

(parted) quit                                                          

Information: You may need to update /etc/fstab.



root@cana:~#

Hint:

resizepart 1 to resize /dev/sda1

-0 resizes it to the end of the disk. - Indicates that it should count from the end of the disk, not the start. This makes -0 the last sector of the disk - which is suitable when you want to make it as big as possible.

If we type df -H it will still showing the old size:

Bash:

root@cana:~# df -H

Filesystem      Size  Used Avail Use% Mounted on

/dev/sda1       271G  240G   18G  94% /

udev             11M     0   11M   0% /dev

tmpfs           1.3G  8.8M  1.3G   1% /run

tmpfs           3.2G   25k  3.2G   1% /dev/shm

tmpfs           5.3M     0  5.3M   0% /run/lock

tmpfs           3.2G     0  3.2G   0% /sys/fs/cgroup

root@cana:~#

Secondly, we need to use resize2fs to extend the volume:
(The file system meta information needs to indicate the size of the disk, and resize2fs updates this.)

Bash:

root@cana:~# resize2fs /dev/sda1

resize2fs 1.42.12 (29-Aug-2014)

Filesystem at /dev/sda1 is mounted on /; on-line resizing required

old_desc_blocks = 16, new_desc_blocks = 29

The filesystem on /dev/sda1 is now 117964544 (4k) blocks long.



root@cana:~#

Connecting using PuTTY on Windows workstations
Configuring PuTTY
1. In PuTTY, under Session, enter your Host Name
2. Under Connection choose Data
3. Enter your username as the Auto-login username
4. Under SSH, choose 2 from Preferred SSH Protocol Version
5. Under SSH -> Auth, you will need to specify where your private key can be found. Remember this is where you saved the private key on your local computer. Click Browse to locate the file on your computer.
6. Under Sessions, type a name (such as "my site") in the Saved Sessions box and click Save.
Connecting using SSH on Linux or OSX workstations
Use the ssh command to connect to your instance. Specify your username and the external IP address for the instance that you want to connect to.

Download Prive Key from client area and save it to your workstation

For this example, the private key is at ~/.ssh/my-ssh-key.

ssh -i ~/.ssh/my-ssh-key USERNAME@IP_ADDRESS

where:
- USERNAME is your username
- IP_ADDRESS is the IP for your Cloud Server.
If the connection is successful, you can use the terminal to run commands on your instance.

When you are done, use the exit command to disconnect from the instance.
How to create a .ppk from private key on Windows
Using a Public/Private key to authenticate when logging into SSH can provide added convenience or added security. The Public/Private key can be used in place of a password so that no username/password is required to connect to the server via SSH. Instead the unique public and private key provide the secure authentication. The keys may also be generated with a different password from your cpanel password if desired.

Generate a ppk file
1. Download and open PuTTYgen here.
2. Click Load
3. Locate the private SSH key that you have downloaded. Note: You will need choose to display All Files* from the menu to the right of the File Name field.
4. Click the Save private key button to create the ppk file.