This is just a very quick and basic guide on how you can have multiple cPanel accounts on the same IP address that’s not the default shared IP address.
One benefit of spreading cPanel accounts over multiple IP addresses for example would be to reduce the impact of poor mail deliverability should one account on a particular IP address start sending out spam. Another real world benefit that springs to mind is if you were to suffer a DDoS attack that could not be mitigated, your provider is likely to “null-route” (take offline) the IP address under attack. In which case it’s better to have 100 accounts spread over 5 IP addresses rather than all on one IP address.
As we know in WHM you can only have one shared IP address set in “Basic WebHost Manager® Setup” which is the default for newly created cPanel accounts.
Let’s say you have the following IP Addresses and domains… 10.10.10.2 – Main Shared IP (Shared for aaa.benyarwood.co.uk – bbb.benyarwood.co.uk – ccc.benyarwood.co.uk) 10.10.10.3 – Currently dedicated to benyarwood.co.uk
… and you want to put bbb.benyarwood.co.uk on 10.10.10.3 by going to “Change Site’s IP Address” but the option is greyed out because it’s already dedicated to benyarwood.co.uk.
So how do I put multiple cPanel accounts on the same IP address?
The “trick” (it really is very simple) is to: 1) Go to Basic WebHost Manager® Setup 2) Change the “The IPv4 address (only one address) to use to set up shared IPv4 virtual hosts.” to be 10.10.10.3 3) Go to Change Site’s IP Address and now 10.10.10.3 should no longer be greyed out. 3a) If it is still greyed out then simply change to another IP address, click “Change” and then go back to the drop-down box and it should now definitely be available to select. 4) Repeat step 1 and 2 to change the default main shared IP address back to what it was before.
It should be noted that when changing IP addresses of websites you could disrupt visitors accessing the website due to DNS cache / propagation times.
If you’re running a shared web-hosting server then you may occasionally have the odd request by a user to relay their mail through their chosen relayer (such as MailGun, Sendgrid, Mailjet etc). This guide will assist you in setting up your WHM to relay different domains via Multiple SmartHosts.
cPanels Blog here explains very well what a SmartHost is. We are going to be following the content of this guide somewhat below with a few extra steps to allow us to specify the domains.
Note: This requires root access to WHM to complete.
Setting up Multiple SmartHosts.
We will assume you’ve already added the domain to your chosen SmartHost(s) control panel, verified the domain and received the appropriate SMTP details to start relaying mail.
In WHM -> Exim Configuration Manager
Login to WHM, go to Exim Configuration Manager, select the Advanced Tab and find the AUTH section similar to the image below.
And that’s it for the WHM side of things so go ahead and save the configuration.
Multiple SmartHosts – File Modifications in SSH / Terminal
We need to edit a few files so go ahead and open up an SSH session or you can use the Terminal inside WHM.
Let’s start by creating a new file in the etc directory called exim_smarhosts, i.e. /etc/exim_smarthosts
It should be quite clear but the purpose of this file is to specify the domains and their associated SMTP credentials. In the example below I have demonstrated my own domain. In this file you only need to add the domains that will be relayed via SmartHost, any domains not specified will continue to be sent out normally through your own server.
That’s it! We just need to rebuild the exim configuration to perform a quick syntax check and activate the changes.
/scripts/buildeximconf
At this point I’d recommend heading into cPanel -> Webmail for one of the domains and sending a test email to an outside recipient to check delivery works okay. Also check that you can still send mail from accounts that AREN’T being relayed.
ConfigServer Security & Firewall (CSF) is great, but the email alerts can certainly be a little overwhelming so here’s a very quick, dirty copy + paste to disable the most of the common email alerts sent out by CSF.
Now depending what you’re hosting, you might want to keep some of these alerts enabled, but some of them are just unnecessary. For example, any server with a public-facing IP address will be port-scanned and have its SSH port brute-forced. In an ideal world we’d have SSH locked down via access-lists with the port closed to public but it’s not always achievable. In this case not many people need to know if an IP address was blocked 5 times for failing to login to their SSH service so long as adequate steps have been taken to protect the service.
You should definitely read the csf.conf file in-depth for further explanation of what each one of these parameters does within CSF but we’ll go ahead and assume you know what these do and that you don’t particularly want the email notifications!
Go ahead and open up SSH to your server. These commands should be run as root.
First you’ll want to make a backup of the your /etc/csf/csf.conf file just in case anything goes wrong or stops working.
cp /etc/csf/csf.conf /etc/csf/csf.conf-bak
Next up just paste the following into your SSH terminal.
sed -i 's/LOGFLOOD_ALERT = "[0-9]*"/LOGFLOOD_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/LF_PERMBLOCK_ALERT = "[0-9]*"/LF_PERMBLOCK_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/LF_NETBLOCK_ALERT = "[0-9]*"/LF_NETBLOCK_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/LF_EMAIL_ALERT = "[0-9]*"/LF_EMAIL_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/LF_SSH_EMAIL_ALERT = "[0-9]*"/LF_SSH_EMAIL_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/LF_SU_EMAIL_ALERT = "[0-9]*"/LF_SU_EMAIL_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/LT_EMAIL_ALERT = "[0-9]*"/LT_EMAIL_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/RT_RELAY_ALERT = "[0-9]*"/RT_RELAY_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/RT_AUTHRELAY_ALERT = "[0-9]*"/RT_AUTHRELAY_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/RT_LOCALRELAY_ALERT = "[0-9]*"/RT_LOCALRELAY_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/RT_LOCALHOSTRELAY_ALERT = "[0-9]*"/RT_LOCALHOSTRELAY_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/CT_EMAIL_ALERT = "[0-9]*"/CT_EMAIL_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/PT_USERKILL_ALERT = "[0-9]*"/PT_USERKILL_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/PS_EMAIL_ALERT = "[0-9]*"/PS_EMAIL_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/AT_ALERT = "[0-9]*"/AT_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/AT_ALERT = "[0-9]*"/AT_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/AT_ALERT = "[0-9]*"/AT_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/PORTKNOCKING_ALERT = "[0-9]*"/PORTKNOCKING_ALERT = "0"/' /etc/csf/csf.conf
sed -i 's/LF_DIRWATCH = "[0-9]*"/LF_DIRWATCH = "0"/' /etc/csf/csf.conf
sed -i 's/PT_LOAD = "[0-9]*"/PT_LOAD = "0"/' /etc/csf/csf.conf
sed -i 's/PT_LIMIT = "[0-9]*"/PT_LIMIT = "0"/' /etc/csf/csf.conf
sed -i 's/PT_USERPROC = "[0-9]*"/PT_USERPROC = "0"/' /etc/csf/csf.conf
sed -i 's/PT_USERMEM = "[0-9]*"/PT_USERMEM = "0"/' /etc/csf/csf.conf
sed -i 's/PT_USERTIME = "[0-9]*"/PT_USERTIME = "0"/' /etc/csf/csf.conf
So, if you’ve found this guide then you probably already know what AmazonSES and SmartHosts are. In this guide I’ll demonstrate how to specifiy certain domains to be relayed through an AmazonSES SmartHost.
cPanels Blog here explains very well what a SmartHost is. We are going to be following the content of this guide somewhat below with a few extra steps to allow us to specify the domains.
Note: This requires root access to WHM to complete.
Configuring the AmazonSES SmartHost in WHM.
We’ll be jumping right into the WHM/Exim Configuration here, this guide assumes you have already set-up your AmazonSES account, verified your domain and added an “identity” for sending test emails to.
Prepare your AmazonSES SMTP Details. You will need: SMTP Host (server name): Usually ends amazonaws.com In this example I will be using “email-smtp.eu-west-2.amazonaws.com” however you MUST use the one specified in your account. SMTP Username and SMTP Password
Classic Console.
In WHM -> Exim Configuration Manager
Login to WHM, go to Exim Configuration Manager, select the Advanced Tab and find the AUTH section similar to the image below.
Copy in the contents of the box below, but change the USERNAME and PASSWORD to your SMTP Username and Password provided in the Amazon SES Management Console.
Note: If your server has multiple IP addresses then you want to add each IP address to this line which would then look like this (obviously replacing 1.1.1.1 and 1.1.1.2 here with your public IP addresses)
And that’s it for the WHM side of things so go ahead and save the configuration.
AmazonSES SmartHost File Modifications in SSH / Terminal
We need to edit a few files so go ahead and open up an SSH session or you can use the Terminal inside WHM.
Let’s start with /etc/exim.conf.local
Find the @CONFIG@ line and add the below inside it.
# Added for Amazon SES
hostlist smart_hosts = lsearch;/etc/smarthosts
###
Save and exit.
Here’s my example (note the @AUTH@ part should already be populated with the changes made earlier, we are only added the above hostlist line underneath @CONFIG@)
Next up is the /etc/smarthosts file, this won’t exist already so you need to create the file. This is the file which specifies which domains on your server will be relaying through the AmazonSES SmartHost. Don’t forget that you must create the domain the Amazon SES Management Console and verify the domain using CNAME records first!
Copy the following into the file but replace domain1.com and domain2.com with the actual domains on your server.
Replace Amazon_SES_Server with the SMTP Host shown to you in the Amazon SES Management Console.
# Added for Amazon SES
domain1.com: Amazon_SES_Server
domain2.com: Amazon_SES_Server
###
Finally we want to create /etc/staticroutes – this will contain the same contents as your /etc/smarthosts file. The easiest way to do this is just copy the file with:
cp /etc/smarthosts /etc/staticroutes
That’s it! We just need to rebuild the exim configuration to perform a quick syntax check and activate the changes.
/scripts/buildeximconf
To confirm, what we’ve just configured is to have emails sent from the domains specified in /etc/smarthosts and /etc/staticroutes to be relayed through AmazonSES. All other domains not specified will continue to be sent directly from your server.
At this point I’d recommend heading into cPanel -> Webmail for one of the domains and sending a test email to an outside recipient (or the identity you’ve set-up in AmazonSES!) to check delivery works okay.
Additional notes: I have discovered that upon performing these changes when you go back to Exim Configuration Manager you might see the following warning:
I set this to contain just “amazonses.com” and the warning disappeared. I then removed it and saved the configuration again and the warning was still gone. *Shrugs*.
Remember to add the following to the SPF record of any domains that will be relaying through the AmazonSES SmartHost.
