IPv6 Setup for Netgear R6100 with Xfinity

1. Access the Router Interface
   • Connect to your R6100 network.
   • Open a browser and go to http://www.routerlogin.net
   • Login with your credentials (default is admin / password unless changed).
2. Navigate to IPv6 Settings
   • Go to Advanced > Advanced Setup > IPv6.
3. Choose the Right Connection Type
   • For Xfinity, start with Auto Detect.
   • If that fails, try Auto Config or DHCP.
   • Avoid 6to4 Tunnel, PPPoE, or Fixed unless you know your ISP requires it.
4. Prefix Delegation
   • If available, set Prefix Length to /64.
   • Enable Router Advertisement (RA).
   • Disable “Allow PD/Address Release” to prevent lease drops during rebinds.
5. LAN Configuration
   • Enable Address Autoconfiguration.
   • Optionally enable DHCPv6 Server with a range like ::1000 to ::2000.

🧠 Pro Tips

• Firmware Check: Make sure your R6100 is running the latest firmware. Older versions may mishandle IPv6 leases.
• Fallback Plan: If IPv6 causes instability, disable it temporarily and rely on IPv4 until Xfinity’s rollout stabilizes.
• Monitoring: Use tools like test-ipv6.com to verify your IPv6 connectivity and DNS resolution.

✅ IPv6 Diagnostic Checklist (R6100 + Xfinity)

1. Firmware Version
   • Check for latest firmware: Advanced > Administration > Firmware Update
   • If outdated, download from Netgear’s support site and update manually.
2. WAN IPv6 Lease
   • Go to Advanced > Advanced Setup > IPv6
   • Confirm WAN IPv6 address is assigned (should start with 2601: or similar for Xfinity)
   • Note lease duration and renewal behavior.
3. LAN IPv6 Distribution
   • Ensure LAN clients are receiving IPv6 addresses (check with ipconfig or ifconfig)
   • Confirm prefix delegation is working (/64 is typical)
4. DNS Resolution
   • Test IPv6 DNS: nslookup google.com should return IPv6 records (AAAA)
   • If not, check DNS settings—try using Cloudflare (2606:4700:4700::1111) or Google (2001:4860:4860::8888)
5. Connectivity Test
   • Visit test-ipv6.com to verify full IPv6 functionality
   • Look for “Your IPv6 connectivity is fine” and note any warnings

🧪 Benchmark Script (Windows PowerShell)

Write-Host "Testing IPv6 Connectivity..." -ForegroundColor Cyan
Test-Connection -ComputerName ipv6.google.com -Count 4 -Protocol ICMPv6

Write-Host "`nChecking IPv6 DNS Resolution..." -ForegroundColor Cyan
Resolve-DnsName google.com -Type AAAA

Write-Host "`nListing IPv6 Addresses on Local Interfaces..." -ForegroundColor Cyan
Get-NetIPAddress -AddressFamily IPv6 | Format-Table InterfaceAlias,IPAddress,PrefixLength

This script checks:

• ICMPv6 ping to Google
• DNS resolution for IPv6
• Local IPv6 address assignment