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Upgrading an Ubuntu server on UpCloud to add more CPU, Memory and Disk Space

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Upgrading an Ubuntu server on UpCloud to add more CPU, Memory and Disk Space

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If you have not read my previous posts I have now moved my blog from Vultr to the awesome UpCloud host (signup using this link to get $25 free credit).

Recently I compared Digital Ocean, Vultr and UpCloud Disk IO here and UpCloud came out on top by a long way (read the blog post here). Here is my blog post on moving from Vultr to UpCloud.

Spoiler: UpCloud performance is great.

Upcloud Site Speed in GTMetrix

Why Upgrade

I have 1 CPU, 1 GB memory and 50GB storage and it is running well?  I have PHP child workers set up and have set up the preferred use of memory over swap file usage.

View of htop querying processes on Ubuntu

Before UpCloud, when I had 512MB ram on Vultr I had multiple NGINX crashed a day so I used a bash script and scheduled a cron job to clear memory cache when memory fell below 100MB (view the script here).  To further increase the speed of the WordPress I have configured the OS to use memory over the disk.  About once a day free memory falls below 100MB (this is not a problem as my script clears cached items automatically).

Graph of memory falling below 100MB every day

I’d like to add more memory as I am working on some things (watch this space) and I will use the extra memory. I’d prefer the server is set up now for the expected workload.

How to Upgrade

This is how I upgraded from 1xCPU/2GB Memory/50GB Storage/2TB Transferred Data to a 2 CPU/4GB Mmeory/80GB Storage/4TB Transferred Data server.

UpCloud Pricing: https://www.upcloud.com/pricing/

Pricing table form https://www.upcloud.com/pricing/

Upgrade an UpCloud VM

I shut down my existing VM. Read this guide to setup a VM.

Login to the UpCloud dashboard, select your server (confirm the server has shut down) and click General Settings, choose the upgrade and click Update.

Upgrade the Server, shut it down the server and choose upgrade

I confirmed the upgrade options (2x CPU, 4096 MB Memory).

Confirm Upgrade Options

Click Update

Upgrade Applied

After 10 seconds you can start your server from the UpCloud server.

I confirmed the CPU upgrade was visible in the VM

Software Tweaks Post Upgrade.

I added these settings to the top of /etc/nginx/nginx.conf to ensure the extra CPU was used.

I increased PHP FPM ( /etc/php/7.2/fpm/php.ini ) to increase the memory usage and child workers. I doubled child workers and max memeory limit.

I restarted NGINX and PHP

I tweaked WordPress max memory limits

MySQL Tweaks: I logged into MySQL

I ran “SHOW GLOBAL STATUS” to view stats

Read more on SHOW GLOBAL STATUS here. Read more on the values here.

I can see NO major errors here (possibly due to UpClouds awesome disk IO) so I won’t be making memory tweaks in MySQL. Sign Up using this link and get $25 credit free on UpCloud and see for yourself how fast they are.

Configure Ubuntu System Memory Usage

Edit /etc/sysctl.conf

Add the following to allow things to sit in ram longer

Snip from: https://www.kernel.org/doc/Documentation/sysctl/vm.txt

Read these pages here and here regarding setting MySQL memory.

Reboot

Resize the disk

The 2x CPU, 4GB memory plan comes with 80GB storage allowance.  My disk at present is 50GB and I will update the size soon following this guide soon.

Upgrade disk from 50gb to 80GB soon

Quick Benchmark

I used loader.io to load 500 users to access my site in 1 minute.

HTOP showing 2x busy CPU's running at 60%

The benchmark worked with no errors.

Loader.io Success with 500 concurrent users

This benchmark was performed with no Cloudflare caching. I should get Cloudflare caching working again to lower the average response time. I loaded my website manually in Google Chrome while loader.io threw 500 users at my site and it loaded very fast.

Conclusion

After a few days, I checked my memory logs and there were no low memory triggers (just normal internal memory management triggers). Ubuntu was happier.

No Low memory low triggers

This graph was taken before I set “vm.vfs_cache_pressure” so I will update this graph in a few days.

I hope this guide helps someone.

Please consider using my referral code and get $25 credit for free.

https://www.upcloud.com/register/?promo=D84793

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Revision History

1.0 Initial Post

Wordfence Security Plugin for WordPress

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WordFence is a great security plugin for WordPress that allows you to secure your WordPress installation and prevent brute force attacks, rate-limit visitors (or Bots), block banned IP’s that are accessing your site and more.

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Fyi

20th Dec 2017: Wordfence report Backdoor in Captcha Plugin Affects 300K WordPress Sites

Backup

Before I started I performed a quick mysql backup from the command line to ensure my WordPress is backed up. Read my guide on installing WordPress from the command line (here) and securin Ubuntu (here).

Don’t forget to backup your WordPress files.

Download and extract WordFence

I downloaded and installed the Wordfence plugin via command line. I visited https://wordpress.org/plugins/wordfence/ and got the plugin URL for the latest version (e.g https://downloads.wordpress.org/plugin/wordfence.6.3.19.zip).

I downloaded the plugin zip file from the command line to my WordPress plugins folder. Read my guide (here) on managing WordPress from the command line.

Now the Wordfence plugin can be activated in WordPress.

Activate Wordfence

Enter your email to receive Wordfence alerts.

WordFence EmmiL Alerts

Your Wordfence Dashboard will show local and global issues and statistics.

WordFence Dashboard

I set these default Wordfence options.

ON

More Wordfence Options

More Options

Set Permissions (for Firewall)

You may need to create a log folder (e.g /www/wp-content/wflogs/)  and set permissions to allow Wordfence to work.

Now I can enable the Wordfence firewall via the WordFence plugin at /wp-admin/admin.php?page=WordfenceWAF

Wordfence Firewall

Don’t forget to configure the Wordfence firewall.

WordFence Firewall

Firewall Install Options

I do not have FTP setup so I’ll do a manual install based on these instructions.

 

WordPress Install Options

I manually added this to my ~/nxinx/sites-available/default config.

I added this to my nginx config.

This did not work as specified in the official Wordfence docs (https://docs.wordfence.com/en/Web_Application_Firewall_FAQ#NGINX) so I added the following.

Accessing a test /test.user.ini file in a web browser returns a 403  (always test access)

I added this to my active php.ini configuration file.

I restart PHP.

I added my IP to the Wordfence whitelist textbox to ensure I am not blocked: /wp-admin/admin.php?page=WordfenceSecOpt 

Tip: Grab your IPV4 address from https://ipv4.icanhazip.com/

Recent Wordfence Scan Summary (1st Scan)

Wordfence Dashboard allows you to see local and global stats.

Recent Scan

Wordfence (In Progress) Scan summary.

Scan Summary

My Issues

Wordfence alerted me that I needed to update WordPress and some plugins  (see my guide on installing and managing your WordPress via the Command Line here).

I updated my WordPress core files (via the command line).

I updated my  WordPress plugins (via the command line).

Output:

I manually updated my WordPress theme (from my.studiopress.com website) and uploaded via SSH

I could then SSH into my server and extract the theme.

Wordfence Dashboard

Wordfence allows you to see worldwide Blocked IP’s by the Wordfence network.

IPs

You can also see local successful or failed login attempts. The Ukraine IP 91.200.12.49 tried to log in to my WordPress installation but was banned globally as it was seen unsuccessfully logging into 900 other global servers, good work Wordfence.

Failed Logins

Attacks blocked locally.

Stats

View global WordPress attacks by countries

Global Attack Stats

Wordfence Features I like

  • Finding abandoned plugins
  • See Globally banned IP’s
  • See local failed login attempts
  • Brute force protection.
  • Stats on local blocked events.
  • Identification of old files.
  • Simple reports.

Wordfence Features I don’t like

  • Your mouse must be active in the window for scans to complete/seen.
  • Setup firewall almost requires FTP.

Wordfence: 7.02 updated (listed here)

Revised Dashboard looks nice

Wordfence 702

More to come, I will update this guide over time.

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Revision Historyv1.2 added info on Wordfence 7.0.2

v1.1 added info on Captcha plugin backdoor detected by Wordfence

v1.0 Initial Post

etc

Installing Redis 3.x onto Ubuntu 16.04

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This post will show you how to install Redis 3.x onto Ubuntu 16.04

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Redis is a server-side (Lua based) schema-free open source (in Memory) NoSQL Key/Value store database that supports replication between servers. Redis has an Eventual Consistency replication between servers (over Immediate Consistency) between servers. Eventual consistency is evil in some peoples minds, eventual consistency does require different coding considerations (to guaranteed valid data but does offer speed benefits).

Redis is the worlds 9th most popular database behind Oracle, MySQL, Microsoft SQL Server, PostgreSQL, MongoDB, DB2, Microsoft Access, Cassandra. Redis is the most popular key-value store database. View the database trend chart here.

When to use Redis over MySQL or MongoDB

Here is a great guide on when to use Redis over MongoDB. Read my previous guide on building a scalable and secure MySQL Cluster.

Redis has a place where a relational database or NoSQL document stores do not (but it is more work). Read more here.

Redis is great in situations where caching or where memory is available on the server.

Free Memory

 

Installing Redis on Ubuntu

Backup the conf file

Open the redis cli (and test it).

Show Redis info (from the redis-cli)

Benchmarking your Redis (quick)

Benchmarking your Redis (slow)

How to save and query a simple key/value integer

How to save and query a simple key/value string

Saving and querying multiple values

Clear all

Add to list (new items at the top)

Add to list (new items at the bottom)

Redis Documentation

redis.io

redis.io/­documentation

https://redis.io/commands/

Redis Crash Course Tutorial

More

5 uses of redis as a database.

Using Redis at scale at Twitter

Digital Ocean guide on Redis

Coming soon PHP access to Redis.

 

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v1.2 Removed reference to Redis 4 in the blurb.

v1.1 Oops, this was Redis 3 and not 4 (thanks, Patrik)

v1.0 Initial version

Securing Ubuntu in the cloud

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It is easy to deploy servers to the cloud within a few minutes, you can have a cloud-based server that you (or others can use). ubuntu has a great guide on setting up basic security issues but what do you need to do.

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If you do not secure your server expect it to be hacked into. Below are tips on securing your cloud server.

First, read more on scanning your server with Lynis security scan.

Always use up to date software

Always use update software, malicious users can detect what software you use with sites like shodan.io (or use port scan tools) and then look for weaknesses from well-published lists (e.g WordPress, Windows, MySQL, node, LifeRay, Oracle etc). People can even use Google to search for login pages or sites with passwords in HTML (yes that simple).  Once a system is identified by a malicious user they can send automated bots to break into your site (trying millions of passwords a day) or use tools to bypass existing defences (Security researcher Troy Hunt found out it’s child’s play).

Portscan sites like https://mxtoolbox.com/SuperTool.aspx?action=scan are good for knowing what you have exposed.

You can also use local programs like nmap to view open ports

Instal nmap

Find open ports

Limit ssh connections

Read more here.

Use ufw to set limits on login attempts

Only allow known IP’s access to your valuable ports

Delete unwanted firewall rules

Only allow known IP’s to certain ports

Also, set outgoing traffic to known active servers and ports

Don’t use weak/common Diffie-Hellman key for SSL certificates, more information here.

More info on generating SSL certs here and setting here and setting up Public Key Pinning here.

Intrusion Prevention Software

Do run fail2ban: Guide here https://www.linode.com/docs/security/using-fail2ban-for-security

I use iThemes Security to secure my WordPress and block repeat failed logins from certain IP addresses.

iThemes Security can even lock down your WordPress.

You can set iThemes to auto lock out users on x failed logins

Remember to use allowed whitelists though (it is so easy to lock yourself out of servers).

Passwords

Do have strong passwords and change the root password provided by the hosts. https://howsecureismypassword.net/ is a good site to see how strong your password is from brute force password attempts. https://www.grc.com/passwords.htm is a good site to obtain a strong password.  Do follow Troy Hunt’s blog and twitter account to keep up to date with security issues.

Configure a Firewall Basics

You should install a firewall on your Ubuntu and configure it and also configure a firewall with your hosts (e.g AWS, Vultr, Digital Ocean).

Configure a Firewall on AWS

My AWS server setup guide here. AWS allow you to configure the firewall here in the Amazon Console.

TypeProtocolPort RangeSourceComment
HTTPTCP800.0.0.0/0Opens a web server port for later
All ICMPALLN/A0.0.0.0/0Allows you to ping
All trafficALLAll0.0.0.0/0Not advisable long term but OK for testing today.
SSHTCP220.0.0.0/0Not advisable, try and limit this to known IP’s only.
HTTPSTCP4430.0.0.0/0Opens a secure web server port for later

Configure a Firewall on Digital Ocean

Configuring a firewall on Digital Ocean (create a $5/m server here).  You can configure your Digital Ocean droplet firewall by clicking Droplet, Networking then Manage Firewall after logging into Digital Ocean.

Configure a Firewall on Vultr

Configuring a firewall on Vultr (create a $2.5/m server here).

Don’t forget to set IP rules for IPV4 and IPV6, Only set the post you need to allow and ensure applications have strong passwords.

Ubuntu has a firewall built in (documentation).

Enable the firewall

Adding common ports

Add a whitelist for your IP (use http://icanhazip.com/ to get your IP) to ensure you won’t get kicked out of your server.

More help here.  Here is a  good guide on ufw commands. Info on port numbers here.

If you don’t have a  Digital Ocean server for $5 a month click here and if a $2.5 a month Vultr server here.

Backups

rsync is a good way to copy files to another server or use Bacula

Basics

Initial server setup guide (Digital Ocean).

Sudo (admin user)

Read this guide on the Linux sudo command (the equivalent if run as administrator on Windows).

Users

List users on an Ubuntu OS (or compgen -u)

Common output

Add User

e.g

Add user to a group

Show users in a group

This will show users in a group

Remove a user

Rename user

Change user password

Groups

Show all groups

Common output

You can create your own groups but first, you must be aware of group ids

Then you can see your systems groups and ids.

Create a group

Permissions

Read this https://help.ubuntu.com/community/FilePermissions

How to list users on Ubuntu.

Read more on setting permissions here.

Chmod help can be found here.

Install Fail2Ban

I used this guide on installing Fail2Ban.

Check Fail2Ban often and add blocks to the firewall of known bad IPs

Best practices

Ubuntu has a guide on basic security setup here.

Startup Processes

It is a good idea to review startup processes from time to time.

Accounts

  • Read up on the concept of least privilege access for apps and services here.
  • Read up on chmod permissions.

Updates

Do update your operating system often.

Minimal software

Only install what software you need

Exploits and Keeping up to date

Do keep up to date with exploits and vulnerabilities

Secure your applications

  • NodeJS: Enable logging in applications you install or develop.

Ban repeat Login attempts with FailBan

Fail2Ban config

Hosts File Hardening

Add

Add a whitelist with your ip on /etc/fail2ban/jail.conf (see this)

Restart the service

Intrusion detection (logging) systems

Tripwire will not block or prevent intrusions but it will log and give you a heads up with risks and things of concern

Install Tripwire.

Running Tripwire

This will scan your system for issues of note

My Output.

More on Tripwire here.

Hardening PHP

Hardening PHP config (and backing the PHP config it up), first create an info.php file in your website root folder with this info

Now look for what PHP file is loadingPHP Config

Back that your PHP config file

TIP: Delete the file with phpinfo() in it as it is a security risk to leave it there.

TIP: Read the OWASP cheat sheet on using PHP securely here and securing php.ini here.

Some common security changes

Don’t forget to review logs, more config changes here.

Antivirus

Yes, it is a good idea to run antivirus in Ubuntu, here is a good list of antivirus software

I am installing ClamAV as it can be installed on the command line and is open source.