Netcup VPS Provider

Netcup is a German hosting provider offering VPS and DNS services. This skill covers DNS API automation and VPS management for ARM G11 servers.

Quick Reference

Resource	URL/Value
DNS API endpoint	https://ccp.netcup.net/run/webservice/servers/endpoint.php?JSON
Customer Control Panel	https://customercontrolpanel.de
Server Control Panel	https://servercontrolpanel.de
Nameservers	root-dns.netcup.net, second-dns.netcup.net, third-dns.netcup.net

DNS API Workflow

1. Login       → Get session ID
2. Query       → infoDnsZone, infoDnsRecords
3. Update      → updateDnsRecords (replaces ALL records)
4. Logout      → End session

Authentication

const response = await fetch(NETCUP_API, {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    action: 'login',
    param: {
      customernumber: '12345',
      apikey: 'abc123...',
      apipassword: 'xyz789...'
    }
  })
});
// Returns: { responsedata: { apisessionid: 'session-id' } }

Get Records

{
  action: 'infoDnsRecords',
  param: {
    customernumber: '12345',
    apikey: 'abc123...',
    apisessionid: 'session-id',
    domainname: 'example.com'
  }
}

Update Records

IMPORTANT: This replaces ALL records in the zone. Always send the complete record set.

{
  action: 'updateDnsRecords',
  param: {
    customernumber: '12345',
    apikey: 'abc123...',
    apisessionid: 'session-id',
    domainname: 'example.com',
    dnsrecordset: {
      dnsrecords: [
        { hostname: '@', type: 'A', destination: '203.0.113.50' },
        { hostname: 'mail', type: 'A', destination: '203.0.113.50' },
        { hostname: '@', type: 'MX', priority: '10', destination: 'mail.example.com' },
        { hostname: '@', type: 'TXT', destination: 'v=spf1 mx ~all' }
      ]
    }
  }
}

API Limitations

Limitation	Impact	Workaround
No per-record TTL	All records share zone TTL	Accept limitation
Slow propagation	~15 min typical	Add wait/retry logic
Full zone updates	Must send ALL records	Cache and merge
Session timeout	15 min sessions	Login per batch

Email DNS Records

Standard records for Mox email server:

Type	Hostname	Value
A	mail	VPS_IP
A	mta-sts	VPS_IP
A	autoconfig	VPS_IP
MX	@	mail.domain.com (priority 10)
TXT	@	v=spf1 mx ~all
TXT	_dmarc	v=DMARC1; p=quarantine; rua=mailto:...
TXT	<selector>._domainkey	v=DKIM1; k=rsa; p=...
TXT	_mta-sts	v=STSv1; id=1
TXT	_smtp._tls	v=TLSRPTv1; rua=mailto:...

External Domains

For domains registered elsewhere (Netim, Gandi, etc.):

1. Add zone in Netcup CCP: Products → Domain → DNS → Add DNS Zone
2. At registrar: Change nameservers to:
   • root-dns.netcup.net
   • second-dns.netcup.net
   • third-dns.netcup.net
3. Wait: 24-48 hours for NS propagation
4. Manage via API: Works like Netcup-registered domains

VPS Management

Reverse DNS (PTR)

Set in Server Control Panel → Network → IPv4/IPv6 address → Edit PTR

Critical for email: PTR must match mail server hostname (e.g., mail.example.com)

Firewall (Port 25)

New VPS may have port 25 blocked:

1. SCP → Firewall
2. Remove "netcup Mail block" policy
3. Save changes

Reference Files

File	When to Read
dns-api.md	API endpoints, authentication, record types
vps-management.md	SCP operations, firewall, rDNS, SSH
account-setup.md	Getting API credentials, adding zones
troubleshooting.md	DNS propagation, API errors, email issues

Common Issues

Problem	Solution
"Domain not found"	Add zone in CCP first (API can't create zones)
Slow propagation	Wait 15+ min; verify with dig @8.8.8.8
Auth failure	Regenerate API key in CCP → Stammdaten → API
Records disappear	API replaces ALL records; always send complete set
Port 25 blocked	Remove "netcup Mail block" in SCP firewall

Verification Commands

# Check A record
dig A mail.example.com @8.8.8.8 +short

# Check MX
dig MX example.com @8.8.8.8 +short

# Check SPF
dig TXT example.com @8.8.8.8 +short | grep spf

# Check DKIM
dig TXT selector._domainkey.example.com @8.8.8.8 +short

# Check DMARC
dig TXT _dmarc.example.com @8.8.8.8 +short

# Check PTR (reverse DNS)
dig -x YOUR_IP +short

# Check from multiple locations
# Use: https://dnschecker.org/

Official Documentation

• Netcup Help Center
• DNS API Wiki
• Firewall Documentation