12-19-2011 12:29 PM - edited 03-01-2019 05:31 PM
Hello,
i would like to get some help on how to make a cisco router supplies addresses to different subnets connected to fastinternet interfaces using "dhcpv6"?
here is my attempt, which is not working;
en
conf t
ipv6 unicast-routing
ipv6 local pool VLAN10-pool AAAA:1::/48 64
ipv6 local pool VLAN20-pool AAAA:2::/48 64
ipv6 dhcp pool DHCPv6POOL
prefix-delegation pool VLAN10-pool
prefix-delegation AAAA:1::23F6:33BA/64 00030001000E84244E70
ipv6 dhcp pool DHCPv6POOL2
prefix-delegation pool VLAN20-pool
prefix-delegation AAAA:2::23F6:33BA/64 00030001000E84244E71
interface FastEthernet0/0
no sh
no ip address
ipv6 enable
ipv6 address FE80::1 link-local
ipv6 address AAAA:1::1/64
ipv6 nd other-config-flag
ipv6 dhcp server DHCPv6POOL
interface FastEthernet0/1
no sh
no ip address
ipv6 enable
ipv6 address FE80::2 link-local
ipv6 address AAAA:2::1/64
ipv6 nd other-config-flag
ipv6 dhcp server DHCPv6POOL2
end
12-20-2011 02:11 PM
Hi Kris,
Prefix delegation feature gives the possibility to centrally control IPv6 addresses used in remote sites using a single DHCP server as shown below :
I guess it is not what you want to do, but just client-server model. Instead try this configuration on the server (IOS > 12.4(24) T) :
ipv6 unicast-routing ! ipv6 dhcp pool VLAN10-pool address prefix AAAA:1::23F6:33BA/64 lifetime infinite infinite dns-server domain-name ! ipv6 dhcp pool VLAN20-pool address prefix AAAA:2::23F6:33BA/64 lifetime infinite infinite dns-server domain-name |
interface FastEthernet0/0 ipv6 address AAAA:1::1/64 ipv6 dhcp server DHCPv6POOL2 rapid-commit |
interface FastEthernet0/1 ipv6 address AAAA:2::1/64 ipv6 dhcp server DHCPv6POOL2 rapid-commit |
Turn IPv6 DHCP on and observe SOLICIT messages from the client and because it is in rapid-commit mode you should see only REPLY from the router to the client.
12-20-2011 03:07 PM
thanks for replying
but i am simulating this network using the latest packet tracer and i am not seeing the address prefix command.
Router>en
Router#conf t
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#ipv
Router(config)#ipv6 un
Router(config)#ipv6 unicast-routing
Router(config)#ipv
Router(config)#ipv6 dh
Router(config)#ipv6 dhcp p
Router(config)#ipv6 dhcp pool VLAN10-pool
Router(config-dhcp)#?
dns-server DNS servers
domain-name Domain name to complete unqualified host names
exit Exit from DHCPv6 configuration mode
no Negate a command or set its defaults
prefix-delegation IPv6 prefix delegation
Router(config-dhcp)#
12-20-2011 06:24 PM
Well, that's another story, packet Tracer do NOT use real IOS but simulates its behavior and in this case IOS 12.4(15)T1
So it works slightly differently, indeed previous versions do not support "address-prefix" command under the dhcp pool, but it works with "prefix-delegation" command :
- Stateful DHCPv6 & ping works (by the way just do ping
and here is the router configuration :
ipv6 dhcp pool dhcp-pool
prefix-delegation pool client-prefix-pool1 lifetime 1800 600
dns-server 2001:DB8:3000:3000::42
domain-name example.com
!
ipv6 dhcp pool dhcp-pool2
prefix-delegation pool client-prefix-pool2 lifetime 1800 600
dns-server 2001:DB8:3000:4000::42
domain-name example.com
!
ipv6 local pool client-prefix-pool1 2001:DB8:1200::/40 48
ipv6 local pool client-prefix-pool2 2001:DB8:2200::/40 48
!
interface FastEthernet0/0
description downlink to clients
ipv6 address 2001:DB8:1200::1/48
ipv6 dhcp server dhcp-pool
!
interface FastEthernet0/1
description downlink to clients
ipv6 address 2001:DB8:2200::1/48
ipv6 dhcp server dhcp-pool2
Try to do it 1st without assigning specific DUID.
ping
I hope this resolves your issue.
AJN
12-22-2011 06:27 AM
Thanks for the detailed explanation.
However, from the router configuration;
ipv6 dhcp pool dhcp-pool
prefix-delegation pool client-prefix-pool1 lifetime 1800 600
dns-server 2001:DB8:3000:3000::42
domain-name example.com
!
ipv6 dhcp pool dhcp-pool2
prefix-delegation pool client-prefix-pool2 lifetime 1800 600
dns-server 2001:DB8:3000:4000::42
domain-name example.com
!
ipv6 local pool client-prefix-pool1 2001:DB8:1200::/40 48
ipv6 local pool client-prefix-pool2 2001:DB8:2200::/40 48
!
interface FastEthernet0/0
description downlink to clients
ipv6 address 2001:DB8:1200::1/48
ipv6 dhcp server dhcp-pool
!
interface FastEthernet0/1
description downlink to clients
ipv6 address 2001:DB8:2200::1/48
ipv6 dhcp server dhcp-pool2
I assume that a pc connected to fa0/0 should get an ipv6 address starting with 2001:DB8:1200:.......
and a pc connected to fa0/1 should get an ipv6 address starting with 2001:DB8:2200:.......
But that is not the case when i examined the pc0 and pc2 config ipv6 address displayed on the snapshots where trey both start with 2001:DB8:1200: ?
Moreover when i simulated the network with the given configuration, i not only got the same problem but both pcs also got the same dns server ?
12-23-2011 10:29 AM
Indeed Kris after a hard time dealing with Packet Tracer discrepancies and instability, the router was only able to assign IPv6 addresses from a single pool independently of the presence of any other pools.
It was even using the same pool after completely erasing it from the configuration and rebooting the router. Obviously it doesn't support multiple instances tied to multiple pools.
In the same time we shouldn't expect Packet Tracer to behave 100% like IOS code because it's not an IOS, it emulates its behavior.
Packet Tracer is an excellent tool to get acquaintance with some technologies and features with just the software as an investment, further you will have to switch to tools like GNS3, and better to real equipments.
Having said that, it looks like the problem is completely out of the scope of Packet Tracer, because even IOS < 12.4(24)T do not support IA (Identity Association) used by DHCPv6 clients to query and manage a particular type of IPv6 addresses (Temporary or Non-Temporary) as shown below on IOS DHCPv6 server :
DHCPv6 server router, IOS 12.4(15)T8:
And on Linux dibbler-client:
The only way to overcome this is to use an IOS supporting IA_NA (>12.4(24) T) as I mentioned in a previous post with different implementation commands of DHCPv6 server using “address-prefix” under “ipv6 DHCP pool”
Here is the configuration I deployed using IOS 12.4(24)T as DHCPv6 server, and I mixed 3 different clients :
DHCPv6#sh ver Cisco IOS Software, 7200 Software (C7200-ADVENTERPRISEK9-M), Version 12.4(24)T2, RELEASE SOFTWARE (fc2) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2009 by Cisco Systems, Inc. Compiled Mon 19-Oct-09 22:53 by prod_rel_team ROM: ROMMON Emulation Microcode BOOTLDR: 7200 Software (C7200-ADVENTERPRISEK9-M), Version 12.4(24)T2, RELEASE SOFTWARE (fc2) DHCPv6 uptime is 1 hour, 39 minutes ... |
And with the following configuration:
! ipv6 unicast-routing ipv6 cef ipv6 dhcp pool pool1 address prefix 2001:DB8:1111::/64 lifetime infinite infinite dns-server 2001:DB8:1201::1 domain-name domain1.com ! ipv6 dhcp pool pool2 address prefix 2001:DB8:2222::/64 lifetime infinite infinite dns-server 2001:DB8:1202::1 domain-name domain2.com ! ipv6 dhcp pool pool3 address prefix 2001:DB8:3333::/64 lifetime infinite infinite dns-server 2001:DB8:1203::1 domain-name domain3.com ! ! interface FastEthernet0/0 ipv6 address 2001:DB8:1111::1/64 ipv6 enable ipv6 nd managed-config-flag ipv6 dhcp server pool1 ! interface FastEthernet0/1 ipv6 address 2001:DB8:2222::1/64 ipv6 enable ipv6 nd managed-config-flag ipv6 dhcp server pool2 ! interface FastEthernet1/0 ipv6 address 2001:DB8:3333::1/64 ipv6 enable ipv6 nd managed-config-flag ipv6 dhcp server pool3 ! |
"ipv6 nd managed-config-flag" is used to instruct client to get IPv6 addresses through DHCPv6
IOS DHCP Server:
The server has assigned each client a different IPv6 address, DNS IPv6 address and a domain name from the corresponding pool configured o the interface:
DHCPv6#sh ipv6 dhcp pool DHCPv6 pool: pool1 Address allocation prefix: 2001:DB8:1111::/64 valid 4294967295 preferred 4294967295 (1 in use, 0 conflicts) DNS server: 2001:DB8:1201::1 Domain name: domain1.com Active clients: 1 DHCPv6 pool: pool2 Address allocation prefix: 2001:DB8:2222::/64 valid 4294967295 preferred 4294967295 (1 in use, 0 conflicts) DNS server: 2001:DB8:1202::1 Domain name: domain2.com Active clients: 1 DHCPv6 pool: pool3 Address allocation prefix: 2001:DB8:3333::/64 valid 4294967295 preferred 4294967295 (1 in use, 0 conflicts) DNS server: 2001:DB8:1203::1 Domain name: domain3.com Active clients: 1 DHCPv6# |
IOS DHCP Client:
FastEthernet0/0 [up/up] FE80::C803:90FF:FE38:0 2001:DB8:1111:0:18D7:1F49:316D:335 DHCPv6Client# DHCPv6Client# DHCPv6Client# DHCPv6Client#sh ipv6 dhcp interface FastEthernet0/0 is in client mode Prefix State is IDLE Address State is OPEN Renew for address will be sent in 10:48:47 List of known servers: Reachable via address: FE80::C804:90FF:FE38:8 DUID: 00030001CA0490380008 Preference: 0 Configuration parameters: IA NA: IA ID 0x00040001, T1 43200, T2 69120 Address: 2001:DB8:1111:0:18D7:1F49:316D:335/128 preferred lifetime INFINITY, valid lifetime INFINITY DNS server: 2001:DB8:1201::1 Domain name: domain1.com Information refresh time: 0 Prefix Rapid-Commit: disabled Address Rapid-Commit: disabled DHCPv6Client# |
Debian Client:
2011.12.23 17:08:48 Client Info Creating SOLICIT message with 1 IA(s), no TA and 0 PD(s) on eth1/3 interface. 2011.12.23 17:08:49 Client Info Processing msg (SOLICIT,transID=0xee14b2,opts: 1 3 8 6) 2011.12.23 17:08:49 Client Info Received ADVERTISE on eth1/3,TransID=0xee14b2, 5 opts: 2 1 3 23 24 2011.12.23 17:08:50 Client Info Processing msg (SOLICIT,transID=0xee14b2,opts: 1 3 8 6) 2011.12.23 17:08:50 Client Info Creating REQUEST. Backup server list contains 1 server(s). 2011.12.23 17:08:51 Client Info Processing msg (REQUEST,transID=0x201d85,opts: 1 3 8 6 2) 2011.12.23 17:08:51 Client Info Received REPLY on eth1/3,TransID=0x201d85, 5 opts: 2 1 3 23 24 2011.12.23 17:08:51 Client Notice Address 2001:db8:2222:0:8d1b:4b3d:24e1:d21e/64 added to eth1/3 interface. 2011.12.23 17:08:51 Client Notice Setting up DNS server 2001:db8:1202::1 on interface eth1/3. 2011.12.23 17:08:51 Client Notice Setting up Domain domain2.com on interface eth1/3. user@debian: user@debian:/etc/init.d$ ip a 1: eth1: link/ether 08:00:27:83:6b:58 brd ff:ff:ff:ff:ff:ff inet6 2001:db8:2222:0:a00:27ff:fe83:6b58/64 scope global dynamic valid_lft 2591973sec preferred_lft 604773sec inet6 fe80::a00:27ff:fe83:6b58/64 scope link valid_lft forever preferred_lft forever user@debian:/etc/init.d$ |
Windows Client:
I hope this will be of help for you as it was for myself
AJN
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