Manual
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242 
30.7 DHCPv6 Troubleshooting 
If the  DHCPv6 clients cannot obtain IPv6 addresses and other network parameters, the 
following procedures can be followed when DHCPv6 client hardware and cables have been 
verified ok: 
   Verify the DHCPv6 server is running, start the related DHCP v6 server function if not 
running; 
   If  the  DHCPv6  clients  and  servers  are  not  in  the  same  physical  network,  verify  the 
router  responsible  for  DHCPv6  packet  forwarding  has  DHCPv6  relay  function.  If 
DHCPv6 relay is not available for the intermediate router, it is recommended to replace 
the router or upgrade its software to one that has a DHCPv6 relay function; 
   Sometimes  hosts  are  connected  to  the  DHCPv6  enabled  switches,  but  can  not  get 
IPv6 addresses. In this situation, it should be checked first whether the ports which the 
hosts  are  connected  to,  are  connected  with  the  port  which  the  DHCPv6  server  is 
connected  to.  If  connected  directly, it  should  be  checked  then whether  the  IPv6 
address pool of the VLAN which the port belongs to, is in the same subnet with the 
address pool configure in the DHCPv6 server; If not connected directly, and any layer 
three DHCPv6 relay is configured between the hosts and the DHCPv6 server, it should 
be  checked  first  whether  an  valid  IPv6  address  has  been  configured  for  the  switch 
interface which the hosts are connected to. If not configured, configure an valid IPv6 
address. If configured, it should be checked whether the configured IPv6 address is in 
the same subnet with the DHCPv6 server. If not, please add it to the address pool. 










