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--- training:sanog33:d-6rd [2018/11/24 05:13] – created philip
+++ training:sanog33:d-6rd [2019/02/13 12:42] (current) – [Background] philip
@@ Line 9: / Line 9: @@
 ===== Preparation =====
-Before we start this lab, remove any previous extra lab configuration on the Access and Customer routers and revert both routers to the configuration as it was at the end of the [[training:sanog32:d-static|Static Lab]]. Check connectivity is working from the Customer router to the rest of the lab network as expected.
+Before we start this lab, remove any previous extra lab configuration on the Access and Customer routers and revert both routers to the configuration as it was at the end of the [[training:sanog33:d-static|Static Lab]]. Check connectivity is working from the Customer router to the rest of the lab network as expected.
 We also need to remove any IPv6 configured on the network as we will be replacing it with 6rd technology. The following subsections describe what needs to be done.
@@ Line 39: / Line 39: @@
-==== Removing IPv6 on the link to the Customer ====
+==== Removing IPv6 configuration on Customer Router ====
-We also need to remove any remaining IPv6 configuration on the link between the Access Router and the Customer Router. Here is an example for the Access Router:
+We also need to remove any remaining IPv6 configuration on the Customer Router:
-  interface FastEthernet0/1
-   description P2P Link to CustX
-   no ipv6 address 2001:DB8:X:20::0/127
-   no ipv6 nd ra suppress all
-  !
-  no ipv6 route 2001:DB8:X:4000::/52 2001:DB8:X:20::1
-  !
-and here is an example for the Customer Router:
   interface FastEthernet0/1
@@ Line 61: / Line 51: @@
   no ipv6 route ::/0 2001:DB8:X:20::
   !
-==== Removing IPv6 configuration on Customer Router ====
 And finally we need to remove the loopback interface from the Customer Router. Remember we created it as an anchor point for testing. Simply do:
@@ Line 71: / Line 59: @@
 We leave `ipv6 unicast-routing` turned on though, as we still will need IPv6 on the router in the next part of the lab.
+===== Configuring the Access Router =====
+==== Originating Customer IPv4 Point-to-Point link in iBGP ====
+The point-to-point link address from the network operator to the customer is normally not carried in the IGP or even in the BGP. However, 6rd uses the point-to-point link address as the basis for the IPv6 prefix generated for 6rd. So the network operator needs to carry the point-to-point link address at least as far as the 6BR router so that the IPv6 tunnel can see its end point on the customer router.
+The simple and scalable way to do this is to put the point-to-point link address into iBGP on the Access Router. Like this:
+  router bgp X0
+   address-family ipv4
+    network 100.68.X.32 mask 255.255.255.252
+  !
+Once you have done this, connect to the Core and Border routers to make sure that you now see this point to point link address in the BGP. And check that connectivity works from the Border router by trying to ping the end point on the Customer router:
+  BX# ping 100.68.X.34
+If there is no answer, check the BGP table, and that there is a default route on the Customer router point back to the Access router.
+==== Removing IPv6 on the Access Router link to the Customer ====
+We also need to remove any remaining IPv6 configuration on the link between the Access Router and the Customer Router. Here is an example for the Access Router:
+  interface FastEthernet0/1
+   description P2P Link to CustX
+   no ipv6 address 2001:DB8:X:20::0/127
+   no ipv6 nd ra suppress all
+  !
+  no ipv6 route 2001:DB8:X:4000::/52 2001:DB8:X:20::1
+  !
 ===== Setting up 6rd =====
@@ Line 80: / Line 99: @@
 What we will set up is something similar to the diagram below.
-{{:training:sanog32:6rd-diagram.png?600|}}
+{{:training:sanog33:6rd-diagram.png?600|}}
 The Customer Router in the diagram is our Customer Router in our network. And the ISP 6rd BR capability will be configured on our autonomous system’s Border Router.
@@ Line 92: / Line 111: @@
 **Note:** Real world examples are not likely to be as constrained as our lab network. If end-users were to get /56s by 6rd, we could set aside a /40 pool, and determine the IPv6 address for 6rd from that pool. For example, if 2001:0DB8:0D00::/40 is used as the pool, then we could create the /56 the end user gets from the final 16 bits of the IPv4 point to point link address. If this was 10.0.10.18, then 10 in decimal becomes **0A**, and 18 in decimal becomes **12** in hexadecimal, making the unique IPv6 address block for the end-site 2001:DB8:0D**0A**:**12**00::/56.
-==== Creating the Tunnel ====
+===== Configuring the 6BR =====
+Now we need to set up the 6BR functionality on the Border router. We need to create the tunnel end point:
+  interface Tunnel0
+   ipv6 enable
+   tunnel source Loopback0
+   tunnel mode ipv6ip 6rd
+   tunnel 6rd ipv4 prefix-len 24
+   tunnel 6rd prefix 2001:DB8:X:C000::/52
+  !
+  ipv6 route 2001:DB8:X:C000::/52 Tunnel0
+The Loopback0 interface already exists - we created that for the iBGP session anchor point earlier on in the workshop.
+Explaining the configuration:
+  * `ipv6 enable` - enables IPv6 on the tunnel interface, but only uses link-local addressing. Global unicast addressing is not needed.
+  * `tunnel source Loopback0` - the 6rd tunnel uses the loopback address of the Border router as the source.
+  * `tunnel mode ipv6ip 6rd` - specifies that this is a 6rd tunnel.
+  * `tunnel 6rd ipv4 prefix-len 24` - drop the first 24 bits, using only the final 8 bits for the 6rd address.
+  * `tunnel 6rd prefix 2001:DB8:X:C000::/52` - the address block the ISP uses for 6rd – the final 8 bits of the IPv4 address will make this up to the /60.
+===== Configuring the Customer Router =====
 Now create the tunnel on the Customer Router. The configuration will look like this:
@@ Line 164: / Line 208: @@
 Refer to the earlier discussion about the “general-prefix”. We have `2001:DB8:6:C220::/60` as the IPv6 subnet created by 6rd. Taking this and appending `::1:0:0:0:0` results in the first subnet to be allocated to the network - the `FastEthernet0/0` interface there is automatically assigned `2001:DB8:6:C221::/64`, with the IPv6 address on the interface being `2001:DB8:6:C221::1/64`.
-===== Configuring the Access Router =====
-The point-to-point link address from the network operator to the customer is normally not carried in the IGP or even in the BGP. However, 6rd uses the point-to-point link address as the basis for the IPv6 prefix generated for 6rd. So the network operator needs to carry the point-to-point link address at least as far as the 6BR router so that the IPv6 tunnel can see its end point on the customer router.
-The simple and scalable way to do this is to put the point-to-point link address into iBGP on the Access Router. Like this:
-  router bgp X0
-   address-family ipv4
-    network 100.68.X.32 mask 255.255.255.252
-  !
-Once you have done this, connect to the Core and Border routers to make sure that you now see this point to point link address in the BGP. And check that connectivity works from the Border router by trying to ping the end point on the Customer router:
-  BRX# ping 100.68.X.34
-If there is no answer, check the BGP table, and that there is a default route on the Customer router point back to the Access router.
-===== Configuring the 6BR =====
-Now we need to set up the 6BR functionality on the Border router.
-As with the customer router, we need to create the tunnel end point:
-  interface Tunnel0
-   ipv6 enable
-   tunnel source Loopback0
-   tunnel mode ipv6ip 6rd
-   tunnel 6rd ipv4 prefix-len 24
-   tunnel 6rd prefix 2001:DB8:X:C000::/52
-  !
-  ipv6 route 2001:DB8:X:C000::/52 Tunnel0
-The Loopback0 interface already exists - we created that for the iBGP session anchor point earlier on in the workshop.
-Explaining the configuration:
-  * `ipv6 enable` - enables IPv6 on the tunnel interface, but only uses link-local addressing. Global unicast addressing is not needed.
-  * `tunnel source Loopback0` - the 6rd tunnel uses the loopback address of the Border router as the source.
-  * `tunnel mode ipv6ip 6rd` - specifies that this is a 6rd tunnel.
-  * `tunnel 6rd ipv4 prefix-len 24` - drop the first 24 bits, using only the final 8 bits for the 6rd address.
-  * `tunnel 6rd prefix 2001:DB8:X:C000::/52` - the address block the ISP uses for 6rd – the final 8 bits of the IPv4 address will make this up to the /60.
 ===== Testing =====
-With the 6BR and the Customer router now set up to support 6rd, trying some IPv4 and IPv6 traceroutes from the Customer router to the backbone Transit providers and out to the Internet. **Hint**: Use the Loopback interface as the source of your traceroutes and pings.
+With the 6BR and the Customer router now set up to support 6rd, try some IPv4 and IPv6 traceroutes from the Customer router to the backbone Transit providers and out to the Internet, for example, to 8.8.8.8 (IPv4) and 2001:4860:4860::8888 (IPv6).
-(Note that the lab doesn’t have IPv6 connectivity, but at least try IPv6 traceroutes into the Transit backbone and to other groups.)
+(Note that if the lab doesn’t have IPv6 connectivity, try IPv6 traceroutes into the Transit backbone and to other groups.)
 What do you see?
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