HP 5500 Ei 5500 Si Switch Series Configuration Guide

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Configuration restrictions and guidelines 
•  You can configure up to six DNS servers, including those with IPv6 addresses, in system view, and 
up to six DNS servers on all interfaces of a device.  
•   A DNS server configured in system view has a higher priority than one configured in interface view. 
A DNS server configured earlier has a higher priority than one configured later in the same view. 
A DNS server manually configured has a higher priority than one dynamically obtained through 
DHCP....

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Step Command Remarks 
3.  Specify a DNS server. 
• (Approach 1) In system view:  
dns server  ip-address 
• (Approach 2) In interface view: 
a.   interface  interface-type 
interface-number 
b.  dns server  ip-address   Use either approach. 
No DNS server is specified by 
default. 
 
Configuring DNS spoofing 
DNS spoofing is effective only when: 
•
  The DNS proxy is enabled on the device. 
•   No DNS server or route to any DNS server is specified on the device. 
To configure DNS spoofing: 
 
Step...

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Step Command Remarks 
2.  Set the DSCP value for DNS 
packets.  dns source-interface
 
interface-type interface-number  By default, no source interface for 
DNS packets is specified. The 
device uses the primary IP 
address of the output interface of 
the matching route as the source 
IP address of a DNS request. 
 
Displaying and maintaining IPv4 DNS 
 
Task Command  Remarks 
Display the static IPv4 domain 
name resolution table. 
display ip host [ |
 { begin | exclude | 
include  }...

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 system-view 
[Sysname] ip host host.com 10.1.1.2 
# Use the ping host.com  command to verify that the device can use static domain name resolution to 
resolve domain name host.com into IP address 10.1.1.2. 
[Sysname] ping host.com 
  PING host.com (10.1.1.2): 
  56  data bytes, press CTRL_C to break 
    Reply from 10.1.1.2: bytes=56 Sequence=1 ttl=128 time=1 ms 
    Reply from 10.1.1.2: bytes=56 Sequence=2 ttl=128 time=4 ms 
    Reply from 10.1.1.2: bytes=56 Sequence=3 ttl=128 time=3 ms 
    Reply...

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Configuration procedure 
Before performing the following configuration, make sure that the device and the host are accessible to 
each other via available routes, and that the IP addresses of the interfaces are configured as 
shown  Figure 43 . 
T

his configuration may vary with DNS servers. The following configuration is performed on a PC running 
Windows Server 2000. 
1.  Configure the DNS server: 
a. Select  Start > Programs  > Administrative Tools  > DNS . 
The DNS server configuration page...

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Figure 45 Adding a host 
 
 
d. On the page that appears, enter host name  host and IP address  3.1.1.1. 
e. Click  Add Host . 
The mapping between the IP address and host name is created. 
Figure 46  Adding a mapping between domain name and IP address 
 
 
2. Configure the DNS client:  

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# Enable dynamic domain name resolution. 
 system-view 
[Sysname] dns resolve 
# Specify the DNS server 2.1.1.2. 
[Sysname] dns server 2.1.1.2 
# Configure com as the name suffix. 
[Sysname] dns domain com 
Verifying the configuration 
# Use the ping host command on the device to verify that the communication between the device and the 
host is normal and that the corresponding destination IP address is 3.1.1.1. 
[Sysname] ping host 
 Trying DNS resolve, press CTRL_C to break 
 Trying DNS server...

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Figure 47 Network diagram 
 
 
Configuration procedure 
Before performing the following configuration, assume that Device A, the DNS server, and the host are 
reachable to each other and the IP addresses of the interfaces are configured as shown in Figure 47. 
1. Configure the DNS server: 
This configuration may vary with different DNS  servers. When a PC running Windows Server 
2000 acts as the DNS server, see  Dynamic domain name resolution configuration example  for 
related configu

ration...

 97 
    Reply from 3.1.1.1: bytes=56 Sequence=1 ttl=126 time=3 ms 
    Reply from 3.1.1.1: bytes=56 Sequence=2 ttl=126 time=1 ms 
    Reply from 3.1.1.1: bytes=56 Sequence=3 ttl=126 time=1 ms 
    Reply from 3.1.1.1: bytes=56 Sequence=4 ttl=126 time=1 ms 
    Reply from 3.1.1.1: bytes=56 Sequence=5 ttl=126 time=1 ms 
 
  --- host.com ping statistics --- 
    5 packet(s) transmitted 
    5 packet(s) received 
    0.00% packet loss 
    round-trip min/avg/max = 1/1/3 ms 
Troubleshooting IPv4 DNS...

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Configuring IRDP 
Overview 
As an extension of the Internet Control Message Protocol (ICMP), the ICMP Router Discovery Protocol 
(IRDP) enables hosts to discover the IP addresses of their neighboring routers and set their default routes. 
 
 NOTE: 
The hosts in this chapter support IRDP. 
 
Background 
Before a host can send packets to another network, it must know the IP address of at least one router on 
the local subnet. The host can obtain this information either through manual configuration, or...