IP Change and Adding Additional IPs: REXE Panel Guide

Changing your server's IP address or adding additional IP addresses may be necessary in various scenarios. In this guide, you'll learn when an IP change is needed, how to request it from the REXE panel, and how to configure multiple IP addresses on Linux.

When is an IP Change Needed?

Blacklist Issue

If your server's IP address has been blacklisted due to spam or malicious activity, email delivery and access to some services may be blocked.

hljs bash

# Check if IP is on a blacklist
for bl in zen.spamhaus.org bl.spamcop.net b.barracudacentral.org; do
  result=$(dig +short 50.113.0.203.$bl)
  if [ -n "$result" ]; then
    echo "BLACKLISTED: $bl"
  fi
done

After a DDoS Attack

If the IP address has been null-routed or its reputation has been damaged after an intense DDoS attack, an IP change may be necessary.

Privacy and Security

If your server's IP address is being targeted or needs to be hidden, an IP change can be a solution.

Geographic Location Change

When an IP address from a different geographic location is needed (CDN, geo-restriction bypass, etc.).

Requesting an IP Change in the REXE Panel

Steps

Log in to the customer panel — sign in to your account at panel.rexe.tr.
Go to the My Servers section.
Select the server for which you want to change the IP.
Go to the Support Request or IP Management section.
Create an IP change request and specify the reason.
The support team will evaluate your request and inform you.

Don't forget to update your DNS records before changing the IP. Update A, PTR, and other relevant records for the new IP. Otherwise, your website and email services may stop working.

Things to Do After IP Change

hljs bash

# 1. Verify new IP
curl -s ifconfig.me

# 2. Update DNS records (at domain registrar)
# A record: @ → new IP
# A record: www → new IP

# 3. Update PTR record (from REXE panel)
# Set PTR record for new IP

# 4. Update firewall rules
sudo ufw status
# Reconfigure rules if necessary

# 5. Check SSL certificate
# Is Let's Encrypt certificate working with new IP?
curl -I https://example.com

Adding Additional IPs

Additional IP addresses are used to run multiple websites, services, or applications on the same server.

Additional IP Use Cases

Multiple SSL certificates: Separate IP for each domain (for older clients without SNI)
Service isolation: Separate IPs for web server, email server
IP-based access control: Access to specific services from specific IPs
Load balancing: Multiple IPs for traffic distribution
Failover: Backup IP when primary IP fails

Requesting Additional IPs from REXE Panel

Log in to the customer panel.
My Servers → Relevant server → IP Management.
Find the Add Additional IP or IP Request option.
Specify how many IPs are needed and the purpose.
After the request is approved, IP addresses are assigned to your server.

Configuring Multiple IPs on Linux

Adding Temporary IPs with ip Command

IPs added with the ip command are lost when the system restarts. Use for testing purposes.

hljs bash

# List current IP addresses
ip addr show
ip addr show eth0

# Add additional IP
sudo ip addr add 203.0.113.237/24 dev eth0

# Add multiple IPs
sudo ip addr add 203.0.113.238/24 dev eth0
sudo ip addr add 203.0.113.239/24 dev eth0

# Remove IP
sudo ip addr del 203.0.113.237/24 dev eth0

# Restart interface
sudo ip link set eth0 down
sudo ip link set eth0 up

# Check routing table
ip route show

# Add default gateway
sudo ip route add default via 203.0.113.1

Persistent IP Configuration with Netplan (Ubuntu 18.04+)

Netplan is Ubuntu's modern network configuration tool.

hljs bash

# View current netplan configuration
cat /etc/netplan/*.yaml

# Edit configuration file
sudo nano /etc/netplan/00-installer-config.yaml

Single IP configuration:

hljs yaml

# /etc/netplan/00-installer-config.yaml
network:
  version: 2
  renderer: networkd
  ethernets:
    eth0:
      addresses:
        - 203.0.113.50/24
      routes:
        - to: default
          via: 203.0.113.1
      nameservers:
        addresses:
          - 8.8.8.8
          - 1.1.1.1

Multiple IP configuration:

hljs yaml

# /etc/netplan/00-installer-config.yaml
network:
  version: 2
  renderer: networkd
  ethernets:
    eth0:
      addresses:
        - 203.0.113.50/24   # Primary IP
        - 203.0.113.237/24   # Additional IP 1
        - 203.0.113.238/24   # Additional IP 2
      routes:
        - to: default
          via: 203.0.113.1
      nameservers:
        addresses:
          - 8.8.8.8
          - 1.1.1.1

hljs bash

# Test configuration (without applying)
sudo netplan try

# Apply configuration
sudo netplan apply

# Verify IP addresses
ip addr show eth0

Configuration with /etc/network/interfaces (Debian/Ubuntu Legacy)

hljs bash

sudo nano /etc/network/interfaces

# Primary IP
auto eth0
iface eth0 inet static
    address 203.0.113.50
    netmask 255.255.255.0
    gateway 203.0.113.1
    dns-nameservers 8.8.8.8 1.1.1.1

# Additional IP (alias)
auto eth0:1
iface eth0:1 inet static
    address 203.0.113.237
    netmask 255.255.255.0

# Additional IP 2
auto eth0:2
iface eth0:2 inet static
    address 203.0.113.238
    netmask 255.255.255.0

hljs bash

# Restart network service
sudo systemctl restart networking

Configuration with nmcli (CentOS/AlmaLinux)

hljs bash

# List current connections
nmcli connection show

# Get connection name
nmcli device status

# Add additional IP
sudo nmcli connection modify "Wired connection 1" \
  +ipv4.addresses "203.0.113.237/24"

# Add multiple IPs
sudo nmcli connection modify "Wired connection 1" \
  +ipv4.addresses "203.0.113.237/24" \
  +ipv4.addresses "203.0.113.238/24"

# Apply changes
sudo nmcli connection up "Wired connection 1"

# Verify IP addresses
ip addr show

Using Multiple IPs with Nginx

To run different websites on different IPs:

hljs nginx

# /etc/nginx/sites-available/site1.conf
server {
    listen 203.0.113.50:80;
    server_name site1.com www.site1.com;
    root /var/www/site1;
    # ...
}

# /etc/nginx/sites-available/site2.conf
server {
    listen 203.0.113.237:80;
    server_name site2.com www.site2.com;
    root /var/www/site2;
    # ...
}

hljs bash

# Test configuration
sudo nginx -t

# Reload Nginx
sudo systemctl reload nginx

Verifying IP Configuration

hljs bash

# List all IP addresses
ip addr show

# Specific interface
ip addr show eth0

# Routing table
ip route show

# Connectivity test
ping -I 203.0.113.237 8.8.8.8

# Check external IP
curl --interface 203.0.113.237 ifconfig.me

# Test all IPs
for ip in 203.0.113.50 203.0.113.237 203.0.113.238; do
  echo -n "$ip: "
  curl --interface $ip -s ifconfig.me
  echo
done

After adding additional IPs, don't forget to set up a separate PTR record for each IP. Especially if you plan to send email, each IP must have a PTR record.

Pay attention to YAML indentation in Netplan configuration. Incorrect indentation will prevent the configuration from being applied. Use 2 spaces for each level.

Conclusion

IP changes and adding additional IPs are an important part of server management. These operations, which can be easily requested from the REXE panel, can be permanently configured on Linux with the ip command or netplan. Remember to update DNS and PTR records for each new IP and review firewall rules.

IP Change and Adding Additional IPs: REXE Panel Guide

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