Asus Router RX3042H User Manual

							
RX3042H User's Manual Troubleshooting
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12  Troubleshooting
This  appendix  suggests  solutions  for  problems  you  may  encounter 
in  installing  or  using  the  RX3042H,  and  provides  instructions  for 
using several IP utilities to diagnose problems. 
Contact  Customer  Support  if  these  suggestions  do  not  resolve  the 
problem.
ProblemTroubleshooting Suggestion
LEDs
Power LED does 
not illuminate after 
product is turned on. Verify that you are using the AC adapter provided with 
the  device  and  that  it  is  securely  connected  to  the 
RX3042H and a wall socket/power strip.
LINK WAN LED 
does not illuminate 
after Ethernet 
cable is attached. Verify  that  an  Ethernet  cable  like  the  one  provided  is 
securely  connected  to  the  Ethernet  port  of  your ADSL 
or  cable  modem  and  the  WAN  port  of  the  RX3042H. 
Make sure that your ADSL or cable modem is powered 
on. Wait 30 seconds to allow the RX3042H to negotiate 
a connection with your broadband modem.
LINK LAN LED 
does not illuminate 
after Ethernet 
cable is attached. Verify  that  the  Ethernet  cable  is  securely  connected  to 
your  LAN  hub  or  PC  and  to  the  RX3042H.  Make  sure 
the PC and/or hub is turned on.
Verify  that  your  cable  is  sufficient  for  your  network 
requirements. A  100  Mbit/sec  network  (100BaseTx) 
should  use  cables  labeled  Cat  5.  10Mbit/sec  cables 
may tolerate lower quality cables.
Internet Access
PC cannot 
access Internet
Use  the  ping  utility,  discussed  in  the  following  section, 
to  check  whether  your  PC  can  communicate  with  the 
RX3042Hʼs LAN IP address (by default 192.168.1.1). If 
it cannot, check the Ethernet cabling. 
If  you  statically  assigned  a  private  IP  address  to  the 
computer,  (not  a  registered  public  address),  verify  the 
following:
•     C h e c k   t h a t   t h e   g a t e w a y   I P  a d d r e s s   o n   t h e  computer  is  your  pu blic  IP  address  (see  the 
Quick Start Guide chapter, Part 2 for instructions 
on viewing the IP information.) If it is not, correct 
the  address  or  configure  the  PC  to  receive  IP 
information automatically. 
						

							
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110

ProblemTroubleshooting Suggestion
PC cannot access 
Internet (cont.) •  
 Verify with your ISP that the DNS server specified 
f o r   t h e   P C   i s   v a l i d .   C o r r e c t   t h e   a d d r e s s   o r 
configure  the  PC  to  receive  this  information 
automatically.
•      Verify  that  a  Network Address  Translation  rule  has  been  defined  on  the  RX3042H  to  translate 
the  private  address  to  your  public  IP  address. 
The  assigned  IP  address  must  be  within  the 
range  specified  in  the  NAT  rules.  Or,  configure 
the PC to accept an address assigned by another 
device  (see  se ction  3.2  “Part  2  —  Configuring 
Your  Computers”).  The  default  configuration 
includes a NAT rule for all dynamically assigned 
addresses within a predefined pool 
PCs cannot display 
web pages on 
the Internet. Verify  that  the  DNS  server  specified  on  the  PCs  is 
correct  for  your  ISP,  as  discussed  in  the  item  above. 
You  can  use  the  ping  utility,  discussed  in  the  following 
section, to test connectivity with your ISPʼs DNS server.
Configuration Manager Program
You forgot/lost 
your Configuration 
Manager user ID 
or password.If  you  have  not  changed  the  password  from  the 
default,  try  using  “admin”  as  the  user  ID  and  “admin” 
for  the  password.  Otherwise,  you  can  reset  the 
device  to  the  default  configuration  by  following  the 
instructions provided in section 10.6.1 “Restore System 
Configuration”.  WARNING:  Resetting  the  device 
removes any custom settings and returns all settings to 
their default values.
Cannot access 
the Configuration 
Manager program 
from your browser. Use  the  ping  utility,  discussed  in  the  following  section, 
to  check  whether  your  PC  can  communicate  with  the 
RX3042Hʼs LAN IP address (by default 192.168.1.1). If 
it cannot, check the Ethernet cabling.
Verify that you are using Internet Explorer 6.0 or newer. 
Support  for  Javascript®  must  be  enabled  in  your 
browser. Support for Java® may also be required.
Verify  that  the  PCʼs  IP  address  is  defined  as  being  on 
the  same  subnet  as  the  IP  address  assigned  to  the 
LAN port on the RX3042H.
Changes to 
Configuration 
Manager are not 
being retained. Be  sure  to  click  on  "
Apply"  button  to  save  any 
changes. 
						

							
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12.1  Diagnosing Problem using IP Utilities
12.1.1  ping
Ping  is  a  command  you  can  use  to  check  whether  your  PC  can 
recognize other computers on your network and the Internet. A ping 
command  sends  a  message  to  the  computer  you  specify.  If  the 
computer receives the message, it sends messages in reply. To use 
it,  you  must  know  the  IP  address  of  the  computer  with  which  you 
are trying to communicate. 
On  Windows-based  computers,  you  can  execute  a  ping  command 
from  the  Start  menu.  Click  the  Start  button,  and  then  click  Run.  In 
the Open text box, type a statement such as the following:
ping 192.168.1.1
Click OK  .  You  can  substitute  any  private  IP  address  on  your  LAN 
or a public IP address for an Internet site, if known. 
If  the  target  computer  receives  the  message,  a  Command  Prompt 
window displays like that shown in Figure 12.1.
Figure 12.1. Using the ping Utility
If  the  target  computer  cannot  be  located,  you  will  receive  the 
message “Request timed out.” 
						

							
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Using  the  ping  command,  you  can  test  whether  the  path  to  the 
RX3042H  is  working  (using  the  preconfigured  default  LAN  IP 
address 192.168.1.1) or another address you assigned.
You  can  also  test  whether  access  to  the  Internet  is  working  by 
typing  an  external  address,  such  as  that  for  www.yahoo.com 
(216.115.108.243). If you do not know the IP address of a particular 
Internet location, you can use the nslookup command, as explained 
in the following section.
From  most  other  IP-enabled  operating  systems,  you  can  execute 
the  same  command  at  a  command  prompt  or  through  a  system 
administration utility.
12.1.2  nslookup
You  can  use  the  nslookup  command  to  determine  the  IP  address 
associated  with  an  Internet  site  name.  You  specify  the  common 
name, and the nslookup command looks up the name on your DNS 
server  (usually  located  with  your  ISP).  If  that  name  is  not  an  entry 
in  your  ISPʼs  DNS  table,  the  request  is  then  referred  to  another 
higher-level  server,  and  so  on,  until  the  entry  is  found.  The  server 
then returns the associated IP address.
On  Windows-based  computers,  you  can  execute  the  nslookup 
command from the Start menu. Click the Start button, and then click 
Run. In the Open text box, type the following:
nslookup
Click OK.  A  Command  Prompt  window  displays  with  a  bracket 
prompt  (>). At  the  prompt,  type  the  name  of  the  Internet  address 
you are interested in, such as www.absnews.com.
The  window  will  display  the  associate  IP  address,  if  known,  as 
shown in Figure 12.2. 
						

							
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Figure 12.2. Using the nslookup Utility
There may be several addresses associated with an Internet name. 
This  is  common  for  web  sites  that  receive  heavy  traffic;  they  use 
multiple, redundant servers to carry the same information.
To  exit  from  the  nslookup  utility,  type  exit  and  press    at  the 
command prompt. 
						

							
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RX3042H User's Manual Index
13  Index
 ACL Configuration page, 74
Computers
configuring IP information, 13
Configuration Manager
overview, 25
troubleshooting, 109
Connectors
rear panel, 8
Date and time, changing, 92
Default configuration, 21
Default gateway, 53
DHCP
defined, 45
DHCP Address Table page, 47
DHCP client
defined, 45
DHCP Lease Table page, 49
DHCP server
defined, 45
pools, 45
viewing assigned addresses, 48
DHCP Server Configuration page, 46
Diagnosing problems
after installation, 20
DMZ IP address, 29
DNS, 50
defined, 50 relay, 51
Domain Name System. See DNS
Dynamically assigned IP addresses, 
36
Eth-0 interface
defined, 22
Ethernet cable, 12
Features, 1
Firmware Upgrade page, 101
Firmware upgrades, 101
Front panel, 5
Gateways
in DHCP pools, 45
Gateway
defined, 53
Hardware connections, 11, 12
Host ID, 105
HTTP DDNS, 60
Internet
troubleshooting access to, 109
IP address
in deviceʼs routing table, 58
IP addresses
explained, 105
IP configuration
static, 17
static IP addresses, 17
Windows 2000, 14 
						

							
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Index RX3042H User's Manual

Windows Me, 15
Windows NT 4.0, 16
IP Configuration
Windows XP, 13
IP information
configuring on LAN computers, 13
, 54-58
IP routes
dynamically configuring, 54
IP Routes
defined, 54
LAN IP address, 27
specifying, 27
LAN network mask, 107
LAN subnet mask, 107
LEDs, 7
troubleshooting, 109
Login
to Configuration Manager, 23
MAC address
in Fixed DHCP Lease Table, 49
NAT
defined, 63
NAPT, 65
Overload, 68
PAT, 65
Reverse NAPT, 67
Virtual Server, 67
Navigating, 26
Netmask. See Network mask
Network classes, 107
Network ID, 107
Network interface card, 1
Network mask, 107
Network Setup, 28
Network  Setup  Configuration  page, 
28
Node on network
defined, 27
Notational conventions, 1
nslookup, 112
Packet
filtering, 63
Pages
DHCP Address Table, 47
DHCP Lease Table, 49
DHCP Server Configuration, 46
Firmware Upgrade Upgrade, 101
LAN Configuration, 27
RIP Configuration, 54
Routing Configuration, 57, 58
Static Route Configuration, 56,57,58
System Status, 20
User Password Configuration, 90
Pages ACL Configuration, 74
Parts
checking for, 3
Password 
						

							
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RX3042H User's Manual Index

changing, 90
default, 19, 24
recovering, 111
PC configuration, 13
PC Configuration
static IP addresses, 17
Ping, 111
Power adapter, 12
Primary DNS, 37
Quick Configuration
logging in, 19
Rear Panel, 8
RIP Configuration page, 54
Routing Configuration page, 54, 56
Secondary DNS, 37
Static IP addresses, 17
Static Route Configuration page, 56
Static routes
adding, 57
Statically assigned IP addresses, 45
Subnet masks, 107
System requirements
for Configuration Manager, 23
System requirements, 1
System Status page, 20
Testing setup, 20
Time and date, changing, 92
Troubleshooting, 109
Typographical conventions, 1 Upgrading firmware, 101
User  Password  Configuration  page, 
90
Username
default, 19, 24
WAN DHCP, 29
WAN IP address, 29
Web browser
requirements, 1
version requirements, 23
Web browsers
compatible versions, 23
Windows NT
configuring IP information, 17