Floating IPs
Reserve dedicated public IPv4 and IPv6 addresses. Attach to any cloud compute instance for instant failover and portability.
Floating IPs
Floating IPs are reserved public IP addresses that you can attach to any cloud compute instance in the same region. They enable instant failover, high availability, and seamless IP portability between instances.
Pricing
| Type | Rate | Notes |
|---|---|---|
| Floating IPv4 | $2.72/mo (~₹250/mo) | Dedicated public IPv4 address |
| Floating IPv6 | $1.63/mo (~₹150/mo) | Dedicated public IPv6 address |
Floating IPs are billed monthly regardless of whether they are attached to an instance. Release a floating IP to stop billing.
Subnet Pricing
Need multiple IPs? Request a subnet allocation for bulk pricing.
| Subnet | Usable IPs | Monthly Cost | Per-IP Effective |
|---|---|---|---|
| Single IPv4 | 1 | $2.72 | $2.72 |
| /30 IPv4 | 2 | $5.00 | $2.50 |
| /29 IPv4 | 5 | $11.00 | $2.20 |
| /28 IPv4 | 13 | $25.00 | $1.92 |
| /27 IPv4 | 29 | $45.00 | $1.55 |
| /24 IPv4 | 253 | Custom | Contact sales |
| Subnet | Monthly Cost |
|---|---|
| /64 IPv6 | Included with every instance |
| /56 IPv6 | $3.00/mo |
| /48 IPv6 | $5.00/mo |
IPv4 subnet allocations of /28 and larger require technical justification per APNIC policy. Provide a brief description of how each IP will be used when submitting your request.
Features
- Instant failover — Reassign a floating IP to another instance in seconds via dashboard or API
- Same-region portability — Move IPs between any instances in the same region
- Reverse DNS (rDNS) — Set custom PTR records for your floating IPs
- Dual-stack — Use IPv4 and IPv6 floating IPs side by side
- API managed — Create, attach, detach, and delete via REST API
- No downtime — IP reassignment happens at the network level with zero downtime
How It Works
1. Reserve a Floating IP
From the cloud dashboard or via API, reserve a new floating IP in your chosen region.
2. Attach to an Instance
Attach the floating IP to any running cloud compute instance in the same region. Traffic to the floating IP is routed to the attached instance.
3. Failover
If an instance goes down, detach the floating IP and reattach it to a healthy instance. The IP moves instantly — no DNS propagation delay.
Reverse DNS (PTR Records)
Set custom reverse DNS records for your floating IPs. This is essential for mail servers and services that require proper rDNS.
Setting rDNS
- Navigate to Networking > Floating IPs in the dashboard
- Click the floating IP you want to configure
- Enter your desired PTR record (e.g.,
mail.example.com) - Save — changes propagate within minutes
Ensure your forward DNS (A/AAAA record) matches the PTR record. Mismatched forward and reverse DNS can cause email delivery issues.
rDNS Requirements
- PTR record must resolve to a valid hostname
- The hostname should have a matching A (IPv4) or AAAA (IPv6) record pointing back to the IP
- Changes take effect within 5–15 minutes
- One PTR record per IP address
Use Cases
| Use Case | Why Floating IPs |
|---|---|
| High availability | Instant failover between primary and standby instances |
| Blue-green deployments | Switch traffic between deployment versions without DNS changes |
| Mail servers | Dedicated IP with proper rDNS for email deliverability |
| Load balancer VIP | Static entry point IP that routes to backend instances |
| SSL certificates | IP-based SSL for legacy clients that don't support SNI |
Limits
| Limit | Value |
|---|---|
| Floating IPs per account | 25 |
| Floating IPs per instance | 5 |
| Subnet requests | Via support ticket |
| rDNS propagation | 5–15 minutes |
API Reference
Reserve a Floating IP
curl -X POST https://api.hostupcloud.com/v1/floating-ips \
-H "Authorization: Bearer $API_TOKEN" \
-H "Content-Type: application/json" \
-d '{"region": "in-blr", "type": "ipv4"}'Attach to Instance
curl -X POST https://api.hostupcloud.com/v1/floating-ips/{ip-id}/attach \
-H "Authorization: Bearer $API_TOKEN" \
-H "Content-Type: application/json" \
-d '{"instance_id": "your-instance-id"}'Set Reverse DNS
curl -X PATCH https://api.hostupcloud.com/v1/floating-ips/{ip-id}/rdns \
-H "Authorization: Bearer $API_TOKEN" \
-H "Content-Type: application/json" \
-d '{"ptr": "mail.example.com"}'Next Steps
- Deploy a Cloud Compute instance to attach floating IPs
- Review Network & Connectivity for private networking and bandwidth
- Configure Block Storage for persistent volumes
- Learn about Security & Compliance for firewall rules