HP 5500 Ei 5500 Si Switch Series Configuration Guide

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Configuring UDP helper 
Only the HP 5500 EI switches support configuring UDP helper on Layer 3 Ethernet interfaces. 
The term interface in this chapter refers to Layer 3 interfaces, including VLAN interfaces and 
route-mode (or Layer 3) Ethernet ports. You can set an Ethernet port to operate in route mode by using the 
port  link-mode  route  command (see  Layer 2—LAN Switching Configuration Guide ). 
Overview 
UDP helper functions as a relay agent that conver ts UDP broadcast packets into unicast...

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Step Command Remarks 
2.  Enable UDP helper. 
udp-helper enable  Disabled by default. 
3.  Enable the forwarding of 
packets with the specified 
UDP destination port 
number(s).  udp-helper port
 { port-number | dns | 
netbios-ds  | netbios-ns  | tacacs | tftp 
|  time  }  No UDP port number is specified 
by default. 
4.
  Enter interface view.  interface
 interface-type 
interface-number   N/A 
5.
  Specify the destination server 
to which UDP packets are to 
be forwarded.  udp-helper server...

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# Enable Switch A to receive directed broadcasts. 
 system-view 
[SwitchA] ip forward-broadcast 
# Enable UDP helper. 
[SwitchA] udp-helper enable 
# Enable the forwarding broadcast packets with the UDP destination port 55. 
[SwitchA] udp-helper port 55 
# Specify the destination server 10.2.1.1 on VLAN-interface 1 in public network. 
[SwitchA] interface vlan-interface 1 
[SwitchA-Vlan-interface1] ip address 10.110.1.1 16 
[SwitchA-Vlan-interface1] udp-helper server 10.2.1.1  

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Configuring IPv6 basics 
Only the HP 5500 EI switches support configuring IPv6 basics on Layer 3 Ethernet interfaces. 
The term interface in this chapter refers to Layer 3 interfaces, including VLAN interfaces and 
route-mode (or Layer 3) Ethernet ports. You can set an  Ethernet port to operate in route mode by using the 
port  link-mode  route  command (see  Layer 2—LAN Switching Configuration Guide ). 
Overview 
Internet Protocol Version 6 (IPv6), also called IP next generation (IPng), was...

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Hierarchical address structure 
IPv6 uses hierarchical address structure to speed up route lookups and reduce the IPv6 routing table size 
through route aggregation. 
Address autoconfiguration 
To simplify host configuration, IPv6 supports  stateful and stateless address autoconfiguration. 
•   Stateful address autoconfiguration enables a host to acquire an IPv6 address and other 
configuration information from a server (for example, a DHCP server). 
•   Stateless address autoconfiguration enables...

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A double colon may appear once or not at all in an IPv6 address. This limit allows the device to 
determine how many zeros the double colon represen ts, and correctly convert it to zeros to restore 
a 128-bit IPv6 address. 
An IPv6 address consists of an address prefix and an interface ID, both of which are equivalent to the 
network ID and the host ID of an IPv4 address, respectively. 
An IPv6 address prefix is written in IPv6-address/prefix-length notation where the IPv6-address is 
represented...

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•  Link-local addresses are used for communication among link-local nodes for neighbor discovery 
and stateless autoconfiguration. Packets with li nk-local source or destination addresses are not 
forwarded to other links. 
•   Site-local unicast addresses are similar to private IP v4 addresses. Packets with site-local source or 
destination addresses are not forwarded out of the local site (or a private network). 
•   A loopback address is 0:0:0:0:0:0:0:1 (or ::1). It cannot be assigned to any...

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Figure 52 Converting a MAC address into an EUI-64 address-based interface identifier 
 
 
•  On a tunnel interface 
The lower 32 bits of the EUI-64 address-based interf ace identifier are the source IPv4 address of 
the tunnel interface. The higher 32 bits of the  EUI-64 address-based interface identifier of an 
ISATAP tunnel interface are 0000:5EFE, whereas those  of other tunnel interfaces are all zeros. For 
more information about tunnels, see Configuring tunneling.  
•   On an interface of...

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Address resolution 
This function is similar to the ARP function in IPv4. An IPv6 node acquires the link-layer addresses of 
neighboring nodes on the same link through NS and NA message exchanges.  Figure 53 sh
 ows how 
Host A acquires the link-layer address of Host B on a single link. 
Figure 53  Address resolution 
 
 
The address resolution operates in the following steps: 
1. Host A multicasts an NS message. The source addr ess of the NS message is the IPv6 address of the 
sending interface of...

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1.
 
Host A sends an NS message whose source  address is the unspecified address and whose 
destination address is the corresponding solicited- node multicast address of the IPv6 address to be 
detected. The NS message co ntains the IPv6 address. 
2. If Host B uses this IPv6 address, Host B returns  an NA message. The NA message contains the IPv6 
address of Host B. 
3.  Host A learns that the IPv6 address is being used  by Host B after receiving the NA message from 
Host B. If receiving no NA...