BGP ipv6 in Proxmox

Comments

• RickBakkr Member, Patron Provider, LIR

  February 2025

  Assuming your Proxmox box is acting as the router, rather than using a VM as a router, you can simply enable forwarding in sysctl.conf, and then assign the gateway IP (usually the first or ::1 or something) to a bridge or a VLAN. You can then use the IPs in your VMs, where you specify the IP of your router as the gateway IP.

  Please, feel free to share more information, like a config, if you require more clues.

  Just as a side note: given that you seem to be 100% behind a single provider .. I am assuming you don't have your own ASN and thus are using a private BGP session? If so, why not simply ask your provider to route you the space directly?

  Thanked by 2saobilin wedge1001
• host_c Patron Provider, Top Host, Megathread Squad

  February 2025

  @saobilin said:
  Hello everyone! I am currently using Proxmox and have successfully installed Bird2 and established a BGP connection. If I want to assign my IPv6 range to virtual machines, how should I proceed? Do I need to modify Bird’s configuration, or should I create a new network bridge? I would really appreciate your help!

  @RickBakkr - is absolutely right on this

  @RickBakkr said: Assuming your Proxmox box is acting as the router, rather than using a VM as a router

  Please use a VM for that, you will be much better of

  vyos, pFsense, opnsense, other - any will do a better job + more performance.

  @RickBakkr said: Just as a side note: given that you seem to be 100% behind a single provider .. I am assuming you don't have your own ASN and thus are using a private BGP session? If so, why not simply ask your provider to route you the space directly?

  And this is even better.

  Thanked by 1saobilin
• Andreix Member, Host Rep

  February 2025 edited February 2025

  @RickBakkr said:
  Just as a side note: given that you seem to be 100% behind a single provider .. I am assuming you don't have your own ASN and thus are using a private BGP session? If so, why not simply ask your provider to route you the space directly?

  Meh... there are plenty of wannabe providers (see above) that don't have a real reason for an AS number as they are (and will be) singlehomed. Yet, still, they waste an ASN anyway.

  So, let him play with his ASN. Who knows!? Maybe in future he'll start selling lowend VMs here.

  @saobilin - don't really have a lot of experience with BIRD, but I could help you out with an IOS-like router (FRR for example).

  Thanked by 2saobilin fluffernutter
• saobilin Member

  February 2025

  @RickBakkr said:
  Assuming your Proxmox box is acting as the router, rather than using a VM as a router, you can simply enable forwarding in sysctl.conf, and then assign the gateway IP (usually the first or ::1 or something) to a bridge or a VLAN. You can then use the IPs in your VMs, where you specify the IP of your router as the gateway IP.

  Please, feel free to share more information, like a config, if you require more clues.

  Just as a side note: given that you seem to be 100% behind a single provider .. I am assuming you don't have your own ASN and thus are using a private BGP session? If so, why not simply ask your provider to route you the space directly?

  Thanks for your reply.I have already configured IPv6 forwarding, net.ipv6.conf.all.forwarding = 1, And the vmbr bridge is configured as a gateway for IPv6,this is my vmbr config:
  auto vmbr3
  iface vmbr3 inet6 static
  address 2a14:aaaa:aaaa::1/40
  bridge-ports none
  bridge-stp off
  bridge-fd 0
  But when i ping the ipv6 address i had config in the vm,it shows Destination unreachable: No route.
  Did I do something wrong? Can you help me take a look?Thanks a lot!
• Andreix Member, Host Rep

  February 2025

  Let's break this down step by step.

  Current Bridge Configuration

  Your config looks mostly correct, but there might be some formatting issues. Here's how it should look:

  auto vmbr3
  iface vmbr3 inet6 static
      address 2a14:aaaa:aaaa::1/40
      bridge-ports none
      bridge-stp off
      bridge-fd 0
  

  Required Setup Components

  For IPv6 routing to work properly with Bird2 and Proxmox VMs, you need to ensure:

  • Bird2 is correctly advertising your IPv6 prefix through proper configuration and routing settings
  • Proper routing is established between the bridge interface and virtual machines
  • Virtual machines have the correct network configuration and IPv6 settings

  Verification Steps

  1. Bird2 Configuration

  Make sure your Bird2 configuration includes the IPv6 prefix route:

  protocol static {
      ipv6 {
          import all;
      };
      route 2a14:aaaa:aaaa::/40 via "vmbr3";
  }
  

  2. Diagnostic Commands

  Run these commands on the Proxmox host to gather more information:

  ip -6 route show
  ip addr show vmbr3
  cat /proc/sys/net/ipv6/conf/vmbr3/forwarding
  

  Potential Issues

  The "Destination unreachable: No route" error typically stems from:

  • Routes not properly propagating to the routing table
  • Firewall rules blocking IPv6 traffic
  • Incorrect VM network configuration

  Additional Information Needed

  To provide more specific guidance, please share:

  • Your VM's IPv6 configuration details
  • The output of ip -6 route show from both the host and VM
  • Any firewall rules that might affect IPv6 traffic

  Thanked by 1saobilin
• w3e4r5 Member

  February 2025

  install a router VM will be a nice solution

  Thanked by 1saobilin
• Andreix Member, Host Rep

  February 2025

  @w3e4r5 said:
  install a router VM will be a nice solution

  It's already pretty non-optimal that he uses a server to act as a router... now why would you suggest to make it even worse and move his routing table inside a VM ?

  Thanked by 1saobilin
• saobilin Member

  February 2025

  @Andreix said:
  Let's break this down step by step.

  Current Bridge Configuration

  Your config looks mostly correct, but there might be some formatting issues. Here's how it should look:

  auto vmbr3
  iface vmbr3 inet6 static
      address 2a14:aaaa:aaaa::1/40
      bridge-ports none
      bridge-stp off
      bridge-fd 0
  

  Required Setup Components

  For IPv6 routing to work properly with Bird2 and Proxmox VMs, you need to ensure:

  • Bird2 is correctly advertising your IPv6 prefix through proper configuration and routing settings
  • Proper routing is established between the bridge interface and virtual machines
  • Virtual machines have the correct network configuration and IPv6 settings

  Verification Steps

  1. Bird2 Configuration

  Make sure your Bird2 configuration includes the IPv6 prefix route:

  protocol static {
      ipv6 {
          import all;
      };
      route 2a14:aaaa:aaaa::/40 via "vmbr3";
  }
  

  2. Diagnostic Commands

  Run these commands on the Proxmox host to gather more information:

  ip -6 route show
  ip addr show vmbr3
  cat /proc/sys/net/ipv6/conf/vmbr3/forwarding
  

  Potential Issues

  The "Destination unreachable: No route" error typically stems from:

  • Routes not properly propagating to the routing table
  • Firewall rules blocking IPv6 traffic
  • Incorrect VM network configuration

  Additional Information Needed

  To provide more specific guidance, please share:

  • Your VM's IPv6 configuration details
  • The output of ip -6 route show from both the host and VM
  • Any firewall rules that might affect IPv6 traffic

  Brother, I am very grateful for this, it has worked! Thank you for your help. My excitement is beyond words!!!! In the start,i lost route 2a14:aaaa:aaaa::/40 via "vmbr3";

  Thanked by 1Andreix
• Andreix Member, Host Rep

  February 2025

  @saobilin said:

  @Andreix said:
  Let's break this down step by step.

  Current Bridge Configuration

  Your config looks mostly correct, but there might be some formatting issues. Here's how it should look:

  auto vmbr3
  iface vmbr3 inet6 static
      address 2a14:aaaa:aaaa::1/40
      bridge-ports none
      bridge-stp off
      bridge-fd 0
  

  Required Setup Components

  For IPv6 routing to work properly with Bird2 and Proxmox VMs, you need to ensure:

  • Bird2 is correctly advertising your IPv6 prefix through proper configuration and routing settings
  • Proper routing is established between the bridge interface and virtual machines
  • Virtual machines have the correct network configuration and IPv6 settings

  Verification Steps

  1. Bird2 Configuration

  Make sure your Bird2 configuration includes the IPv6 prefix route:

  protocol static {
      ipv6 {
          import all;
      };
      route 2a14:aaaa:aaaa::/40 via "vmbr3";
  }
  

  2. Diagnostic Commands

  Run these commands on the Proxmox host to gather more information:

  ip -6 route show
  ip addr show vmbr3
  cat /proc/sys/net/ipv6/conf/vmbr3/forwarding
  

  Potential Issues

  The "Destination unreachable: No route" error typically stems from:

  • Routes not properly propagating to the routing table
  • Firewall rules blocking IPv6 traffic
  • Incorrect VM network configuration

  Additional Information Needed

  To provide more specific guidance, please share:

  • Your VM's IPv6 configuration details
  • The output of ip -6 route show from both the host and VM
  • Any firewall rules that might affect IPv6 traffic

  Brother, I am very grateful for this, it has worked! Thank you for your help. My excitement is beyond words!!!! In the start,i lost route 2a14:aaaa:aaaa::/40 via "vmbr3";

  Glad it helped.