Solwise SAR110 User manual

Solwise Ltd .
Advanced Reference Guide for
Solwise SAR110
ADSL Router
Please Note: Incorrect usage of CLI commands
can seriously damage the firmware settings
and configuration of your router to the extent
where you might be unable to reset/restore to
an operable state. We reserve the right to
charge for any faulty router returned for repair
which has user corrupted firmware or settings.
April 11, 2003

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Notification is hereby given that Solwise Ltd. reserves the right to
modify, change, update or revise this document from time to time as
required without the prior obligation to notify any person, company
or organization. Further, Solwise makes no warranty or
representation, either express or implied, with respect to
merchantability, or fitness of its products for a particular purpose.
Solwise Ltd.
13/15 Springfield Way
Anlaby
Hull HU10 6RJ
UK
Tel [phone] (local rate)
Fax [phone]
Email [email protected]
Http www.solwise.co.uk
Copyright
All rights reserved. No part of this document may be reproduced in any form or by any means
without written permission from the product manufacturer.
Changes are periodically made to the information in this document. They will be incorporated in
subsequent editions. The product manufacturer may take improvement and/or changes in the
product described in this document at any time.

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Table of Contents
1Introduction..........................................................9
2Quick Start.........................................................11
3CLI Introduction.................................................12
4Unit Configuration..............................................13
4.1 Default Configuration................................................13
4.1.1 System Sizing Parameters........................17
4.2 Modifying the Unit’s MAC Address and
Serial Number..................................................................19
4.3 Modifying the Unit Configuration via Script
Files..................................................................................19
4.3.1 Notes on Using Script File
Configuration..........................................................20
4.4 Managing Configuration Changes...........................20
4.5 Using FTP/TFTP to Upgrade and Retrieve
the Flash Image...............................................................21
4.5.1 Data configuration Upgrade ......................22
4.5.2 Recovering from a Failed Upgrade ................22
5Interfaces and Operating Mode ........................24
5.1 Interfaces – Overview...............................................24
5.2 Configuring the Ethernet Port ..................................24
5.3 Configuring Virtual Ethernet Interfaces....................27
5.4 Configuring the WAN ATM Port...............................27
5.5 Configuring Permanent Virtual Circuits ...................28
5.5.1 AAL5 Data Encapsulation Method .................29
5.5.2 ATM Service Categories: UBR,
CBR, GFR, NRTVBR and RTVBR ....................30
5.6 Configuring Switched Virtual Circuits (SVCs)..........33
5.7 Configuring PPP Interfaces......................................36
5.7.1 Creating a Login Name and
Password for a PPP Interface.............................37
5.7.2 PPPoE Interfaces........................................38
5.7.3 PPPoA Interfaces........................................39
5.7.4 Checking the IP Address of a PPP
Interface...................................................................40

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5.7.5 Configuring the PPP Auto
start/stop Feature ..................................................40
5.7.6 IP Unnumbered PPP Interfaces...............40
5.8 Configuring the Operating Mode..............................43
5.8.1 Bridge Mode.................................................43
5.8.2 WAN to WAN bridging ...............................46
5.8.3 Router Mode ...................................................46
5.8.4 Bridge Router Autosense (BRAS) ...........49
5.8.5 Zero Installation PPPoE Bridge
(ZIPB) Mode ...........................................................50
6Viewing and Modifying DSL Information...........54
6.1 Modifying the DSL Configuration.............................54
6.2 Viewing DSL Parameters and Statistics..................55
7Configuring IP and Routing Management.........57
7.1 Configuring Routing on LAN Hosts..........................57
7.2 Configuring Routes...................................................57
7.3 Routing Mode ...........................................................58
7.4 RIP ............................................................................59
7.4.1 RIP Global Configuration...........................59
7.4.2 RIP Interface Configuration.......................59
7.5 IGMP.........................................................................60
8Virtual Private Network......................................64
8.1 Overview...................................................................64
8.2 L2TP .........................................................................65
8.3 Configuration details.................................................67
8.4 L2TP Traps...............................................................72
9Configuring DNS Relay.....................................73
9.1 Overview of DNS Relay ...........................................73
9.2 Configuration Details ................................................73
10 Configuring DHCP Server and DHCP
Relay ..............................................................74
10.1 Default DHCP Configuration on the
SAR110 Reference Unit..................................................74
10.2 Configuring Unit as DHCP Server..........................74
10.2.1 Creating DHCP Pools..............................75
10.2.2 Excluding Addresses from a Pool .........77
10.2.3 Modifying and Deleting Pools.................78

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10.2.4 Creating Static DHCP Assignments.............78
10.2.5 Enabling the DHCP Server...........................79
10.2.6 DHCP- DNS Relay Interaction...............80
10.2.7 Viewing DHCP Server Address
Assignments...........................................................80
10.3 Configuring DHCP Relay........................................80
10.3.1 Configuring the DHCP Relay
Interfaces ................................................................80
10.3.2 Specifying the DHCP Server IP
Address ...................................................................81
10.3.3 Enabling DHCP Relay Mode........................81
10.4 Using a DHCP Server on the LAN .........................82
10.5 DHCP Traps............................................................82
10.5.1 Duplicate IP Address Trap......................82
10.5.2 Low Threshold Hit Trap ...........................82
10.6 ForceRenew............................................................83
11 Simple Network Time Protocol..........................84
11.1 Overview .................................................................84
11.2 SNTP implementation details .................................84
11.3 Configuration details ...............................................86
12 Layer 2 Security ................................................88
12.1 Raw Filtering – Overview........................................88
12.1.1 Using Raw Filtering Rules and
Subrules ..................................................................89
12.1.2 Raw Filtering Global Configuration...............91
12.2 Protocol Blocking ....................................................91
12.3 L2 Wall.....................................................................92
12.3.1 Overview.....................................................92
12.3.2 Configuration Files....................................93
12.3.3 AutoDetect Algorithm ...............................93
12.3.4 Assumptions ..............................................94
12.3.5 Sample Configuration Files ..........................94
13 Layer 3 Security ................................................96
13.1 NAT .........................................................................96
13.1.1 Default NAT Configuration on the
SAR110 Unit.............................................................97
13.1.2 Configuring NAT Direction ......................98

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13.1.3 The napt rule .................................................98
13.1.4 The rdr Rule .............................................100
13.1.5 The basic and filter Rules......................102
13.1.6 The bimap Rule.......................................103
13.1.7 The pass Rule .........................................103
13.1.8 Configuring ALGs........................................103
13.1.9 Enabling NAT ..........................................106
13.2 Firewall ..................................................................106
13.2.1 Attack protection .....................................106
13.2.2 Firewall features......................................110
13.2.3 Configuration details...............................111
13.3 IP Filtering and IP Sessions..................................113
13.3.1 Using IP Filtering Rules .........................115
13.3.2 Configuring Time-of- day based
rules 117
13.3.3 IP Sessions – Advanced
Configuration Issues ...........................................120
13.3.4 IP Filtering Global Configuration..........122
14 Usage Control .................................................124
14.1 Overview ...............................................................124
14.2 User Authentication process.................................125
14.3 Configuration using CLI ........................................130
15 Application Security – Surfing Profile..............132
15.1 Surfing Profile........................................................132
15.2 Invoking the Surfing Profile Feature.....................132
15.3 Types of files .........................................................132
15.3.1 Surfing profile - modes of
operation ...............................................................133
15.4 Surfing profile – feature details.............................135
16 Auto-configuration ...........................................136
16.1 AutoDetect.............................................................136
16.1.1 Overview...................................................136
16.1.2 Configuring the Modem to Work with
AutoDetect..............................................................137
16.1.3 AutoDetect Configuration Options..............138
16.1.4 Considerations ............................................140
16.2 Auto-configuration Using ILMI (TR-037) ..............141

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16.2.1 Starting Auto- configuration
through Default ....................................................142
16.2.2 Starting auto- configuration at run
time 144
16.2.3 Viewing auto- configured VCs..............144
16.2.4 Best effort configuration.........................145
16.2.5 VCC change and Cold Start Trap........146
16.2.6 Configuration Conflicts...........................146
16.2.7 Configuration mismatch Traps .............146
16.2.8 Constraints ...............................................146
16.2.9 Recommended parameters
required from network.........................................147
17 Other Device Access Mechanisms .................148
17.1 Simple Network Management Protocol
(SNMP) ..........................................................................148
17.1.1 SNMP Communities...............................148
17.1.2 SNMP Hosts ............................................148
17.1.3 SNMP Traps ............................................149
17.1.4 Providing SNMP Access Across
the Modem............................................................149
17.2 Web-based Interface ............................................150
17.2.1 Accessing the Web- based
Interface.................................................................150
17.2.2 Accessing the Quick
Configuration Page .............................................151
17.2.3 User Instructions .........................................152
17.2.4 Web-based Diagnostics ........................152
17.3 L2 Agent Module...................................................153
18 System Maintenance.......................................155
18.1 Diagnostics............................................................155
18.1.1 Checking IP Connectivity ......................155
18.2 Diagnostics page of the HTTP Agent...................155
18.2.1 Diagnostics - categories ........................155
18.3 ATM Traffic Diagnostics........................................156
18.3.1 OAM F5 CC .............................................157
18.3.2 OAM Loopback ...........................................159
18.4 Traps .....................................................................160

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18.5 Requesting Status and Statistical
Information.....................................................................161
18.6 Viewing complete system configuration...............163
18.7 Managing User Accounts .....................................164
18.7.1 Creating User Accounts.........................164
18.7.2 Deleting User Accounts ..............................165
18.8 Changing the Login Password .............................165
18.9 Modifying System Parameters .............................166
18.10 Configuring Host Name and Domain
Name on the Modem ....................................................166
18.11 Debugging using Memory Location ...................169
18.12 Serial Port Authentication ...................................169
18.12.1 Using CLI Commands .........................169
19 Shell Tutorial ...................................................171
19.1 Shell Tutorial - Overview.......................................171
19.2 Shell Programming Tutorial ..................................172
19.2.1 A First Script.............................................173
19.2.2 Variables...................................................174
19.2.3 IF-ELSE Construct..................................175
19.2.4 Goto...........................................................177
19.2.5 Readout and Search ..............................179
19.2.6 Return........................................................182
19.2.7 Keywords..................................................185
19.2.8 Symbols....................................................185
20 Glossary ..........................................................186

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1 Introduction
This document contains the following chapters:
 Introduction, provides basic information on this
document.
 Chapter 2 shows how to set up, configure, and operate
the SAR110.
 Chapter 3 gives a brief overview of the main features of
the Command Line Interface (CLI).
 Chapter 4 defines and describes the reference unit’s
default configuration, and explains how you can alter the
current configuration using flat files.
 Chapter 5 shows how to configure the unit’s interfaces,
and how to change its operating mode.
 Chapter 6 explains the CLI commands that can be used
to modify and display DSL-related parameters and statistics.
 Chapter 7 shows how to use CLI to configure IP routes.
 Chapter 8 shows how to use the Layer 2 Tunneling
protocol (L2TP) to enable the unit to provide VPN services.
 Chapter 9 shows how to configure the modem as a DNS
relay server.
 Chapter 10 shows how to use CLI to configure the
Dynamic Host Configuration Protocol (DHCP) server and or
client functions.
 Chapter 11 describes the configuration options of the
Simple Network Transfer Protocol.
 Chapter 12 describes raw filtering, protocol blocking and
the L2 Wall feature.
 Chapter 13 details information on configuring NAT,
Firewall and IP Filtering.
 Chapter 14 discusses the new Usage Control feature of
the unit.
 Chapter 15 discusses the surfing profile feature that
provides application security.
 Chapter 16 discussing how auto configuration is possible
with auto detect and TR-37 support.
 Chapter 17 discusses mechanisms for management
access to the modem, using SNMP, Web-based interface,
and L2 Agent.
 Chapter 18 shows how to perform basic maintenance
functions using CLI.
 Chapter 19 helps you understand how to use shell scrips

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to your advantage, and provides a tutorial on shell
programming.
A glossary of terms used in this document is also provided.

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2 Quick Start
See Setup documention supplied with your router

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3 CLI Introduction
See full SAR110 CLI manual.

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4 Unit Configuration
This chapter describes the default configuration programmed into
the flash memory, as well as how to modify the configuration after
boot-up.
4.1 Default Configuration
The unit’s default configuration is established by the factory defaults
file named TEFacs.txt. You customize the default configuration by
modifying this file, then creating and loading a new flash image (a
description of this process and sample factory defaults files are
provided in the Image Handling User Manual). At boot-up, the CLI
commands in this file are automatically executed. Once the unit is
operational, its configuration can be changed interactively using CLI,
or in batch mode by script file upload (described in section ).
The following list describes example settings that may appear in the
default TEFacs.txt:
 CLI user accounts
One superuser account: name = ‘DSL’, password = ‘DSL’
 Maximum number of VCs: 8
 Maximum number of IP sessions: 192
 LAN interfaces
Ethernet port: eth-0, IP address 192.168.7.1, subnet mask 255.255.255.0
 DSL — configured for multimode coding standard
 WAN interfaces
ATM port: atm-0; maximum VCs allowed = 8
ATM VC: aal5-0, lower interface atm-0, VPI = 0, VCI = 38
PPPoE interface: ppp-0, lower interface aal5-0, default route
PPP user name ‘guest’, password ‘guest’, PAP authentication
 RIP — Enabled on PPP interface
 DHCP — enabled with one pool for LAN computers:
Pool ID = 1, address range = 192.168.7.3 to 192.168.7.34,
mask 255.255.255.0
 NAT — enabled with an NAPT rule for translating
local private addresses to the public address assigned to
ppp-0
 Bridging — enabled with ethernet interface defined
as bridgeable

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 IP Filter — enabled, with various rules configured for
high, medium, and low security.
Below lists the CLI commands in the factory defaults file that
configures the unit as a router.
create user name DSL passwd DSL root
modify system logthresh 1
size maxvc 8 max1483vc 8 maxppe 8
modify nbsize maxipsess 192
create ethernet intf ifname eth-0 ip 192.168.7.1
mask 255.255.255.0 inside
modify dsl config gdmt
create atm port ifname atm-0 maxvc 8
create atm trfdesc trfindex 0 NOCLP_NOSCR
create atm vc intf ifname aal5-0 lowif atm-0 vpi
0 vci 38 vcmux
create ppp security ifname ppp-0 CHAP login guest
passwd guest
create ppp intf ifname ppp-0 start lowif aal5-0
droute true PPOA usedhcp false outside usedns
true
create rip intf ifname ppp-0
create dhcp relay intf ifname ppp-0
create nat rule entry ruleid 1 napt
modify nat global enable
modify ipf global pubdefact accept
modify ipf global pvtdefact deny
modify ipf global dmzdefact accept
create ipf rule entry ruleid 10 dir in act deny
destaddr bcast seclevel high
create ipf rule entry ruleid 20 dir in act deny
destaddr eq 255.255.255.255 seclevel high
create ipf rule entry ruleid 30 ifname private
dir in act accept storestate enable seclevel high
medium low

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create ipf rule entry ruleid 40 ifname private
dir out srcaddr self act accept storestate enable
seclevel high medium low
create ipf rule entry ruleid 50 ifname private
dir out inifname dmz transprot eq udp destport eq
num 53 act accept storestate enable seclevel high
medium low
create ipf rule entry ruleid 60 ifname private
dir out inifname dmz transprot eq tcp destport eq
num 53 act accept storestate enable seclevel high
medium low
create ipf rule entry ruleid 70 ifname private
dir out inifname dmz transprot eq tcp destport eq
num 25 act accept storestate enable seclevel high
medium low
create ipf rule entry ruleid 80 ifname private
dir out inifname dmz transprot eq tcp destport eq
num 110 act accept storestate enable seclevel
high medium low
create ipf rule entry ruleid 90 ifname private
dir out inifname dmz transprot eq tcp destport eq
num 21 act accept storestate enable seclevel
medium low
create ipf rule entry ruleid 100 ifname private
dir out inifname dmz transprot eq tcp destport eq
num 80 act accept storestate enable seclevel
medium low
create ipf rule entry ruleid 110 ifname private
dir out inifname dmz transprot eq tcp destport eq
num 23 act accept storestate enable seclevel low
create ipf rule entry ruleid 120 ifname private
dir out inifname dmz transprot eq icmp act accept
storestate enable seclevel low
create ipf rule entry ruleid 130 ifname dmz dir
out inifname private transprot eq tcp destport eq
num 23 act deny seclevel high
create ipf rule entry ruleid 140 ifname dmz dir
out inifname public transprot eq udp destport eq
num 53 act deny seclevel high
create ipf rule entry ruleid 150 ifname dmz dir
out inifname public transprot eq tcp destport eq
num 53 act deny seclevel high
create ipf rule entry ruleid 160 ifname dmz dir
out inifname public transprot eq tcp destport eq
num 21 act deny seclevel high

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create ipf rule entry ruleid 170 ifname dmz dir
out inifname public transprot eq tcp destport eq
num 23 act deny seclevel high medium low
create ipf rule entry ruleid 180 ifname dmz dir
out inifname public transprot eq icmp act deny
seclevel high medium
create ipf rule entry ruleid 190 ifname public
dir out transprot eq tcp destport eq num 23 act
deny seclevel high
create ipf rule entry ruleid 200 ifname public
dir out srcaddr self act accept storestate enable
seclevel high medium low
create ipf rule entry ruleid 210 ifname public
dir in act deny destaddr bcast seclevel medium
create ipf rule entry ruleid 220 ifname public
dir in act deny destaddr eq 255.255.255.255
seclevel medium
create ipf rule entry ruleid 230 ifname public
dir in act deny transprot eq udp destport eq num
7 seclevel high medium
create ipf rule entry ruleid 240 ifname public
dir in act deny transprot eq udp destport eq num
9 seclevel high medium
create ipf rule entry ruleid 250 ifname public
dir in act deny transprot eq udp destport eq num
19 seclevel high medium
create ipf rule entry ruleid 260 ifname public
dir in destaddr self transprot eq tcp destport eq
num 80 act deny seclevel high medium low
create ipf rule entry ruleid 270 ifname public
dir in destaddr self transprot eq udp destport eq
num 53 act deny seclevel high
create ipf rule entry ruleid 280 ifname public
dir in destaddr self transprot eq tcp destport eq
num 53 act deny seclevel high
create ipf rule entry ruleid 290 ifname public
dir in destaddr self transprot eq tcp destport eq
num 21 act deny seclevel high medium low
create ipf rule entry ruleid 300 ifname public
dir in destaddr self transprot eq tcp destport eq
num 23 act deny seclevel high medium low
create ipf rule entry ruleid 310 ifname public
dir in destaddr self transprot eq icmp act deny
seclevel high medium
create ipf rule entry ruleid 320 ifname public
dir in destaddr self transprot eq udp destport eq

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num 53 act accept storestate enable seclevel
medium low
create ipf rule entry ruleid 330 ifname public
dir in destaddr self transprot eq tcp destport eq
num 53 act accept storestate enable seclevel
medium low
create ipf rule entry ruleid 340 ifname public
dir in act deny isipopt yes seclevel high
create ipf rule entry ruleid 350 ifname public
dir in act deny isfrag yes seclevel high
create ipf rule entry ruleid 360 ifname dmz dir
in destaddr self transprot eq tcp destport eq num
80 act deny seclevel high medium
create ipf rule entry ruleid 370 ifname dmz dir
in destaddr self transprot eq tcp destport eq num
21 act deny seclevel high medium
create ipf rule entry ruleid 380 ifname dmz dir
in destaddr self transprot eq tcp destport eq num
23 act deny seclevel high medium
create ipf rule entry ruleid 390 ifname dmz dir
in act accept storestate enable seclevel high
medium low
end
For detailed information on all CLI commands (except modify
nbsize and size, which are described in section ), see the
SAR110CLI Manual.
4.1.1 System Sizing Parameters
The first two lines of the factory defaults file specify “sizing”
parameters. These parameters set upper limits on some of the basic
elements of the system, e.g., the number of VCs or IP sessions.
The sizing parameters are specified using the size and modify
nbsize commands. While these commands are available in CLI,
they are “hidden” from the user; they do not appear in the output of
the help command and are otherwise undocumented. This is
because these commands are only for OEM use; end users should
have no knowledge of these commands.
Because parts of the system, the size and modify nbsize commands must come at the beginning of the
factory defaults file.

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The size command
This command sets upper limits on certain system properties. Its
parameters are:
 maxvc and max1483vc – Maximum number of VCs
(both: default 2)
 maxppe – Maximum number of PPPoE sessions (default
1)
 maxmac – Maximum number of MAC addresses that are
learned by the bridge forwarding table (default 256)
 maxpfrawrule – Maximum number of raw filter rules
(default 8)
 maxpfrawsubrule – Maximum number of raw filter
subrules (default 8)
 maxipfrule - Maximum number of IP filter rules
(default 8)
You should set these parameters in accordance with the anticipated
needs of a typical end user of your product.
The modify nbsize command
This command is used to modify
 the maximum number of IP sessions that can be
active at any given time the TELNET server port
 the FTP server port
 the HTTP server port.
An IP session is a connection between two applications, one running on one of your LAN’s hosts
and the other running on a host on the WAN, e.g., a connection between a host on your LAN
and an Internet web site.
To see the maximum number of IP sessions currently configured or port on which
TELNET, HTTP, FTP servers are running, enter:
$ get nbsize
To limit the maximum number of active IP sessions to 256, enter:
$ modify nbsize maxipsess 256
 To modify the TELNET server port to 9000, enter:
$ modify nbsize telnetport 8000
 To modify the FTP server port to 1000, enter:
$ modify nbsize ftpport 9000

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 To modify the HTTP server port to 8000, enter:
$ modify nbsize httpport 10000
The modify nbsize command does not take effect until the next
system reboot occurs. To initiate a system reboot, enter the
following pair of commands:
$ commit
$ reboot last
4.2 Modifying the Unit’s MAC Address and Serial Number
When you build a software image, it is coded with a default MAC
address and serial number. You can change this data on a particular
unit using the CLI.
Serializing an image
To change the MAC address and serial number on a board, enter:
do serialize AA-BB-CC-DD-FF-12 111122233334444
The MAC address is a 12-digit hexadecimal number, which can be entered with dashes, as
shown, or as a single string. The same MAC address applies to all the unit’s LAN-side
interfaces (e.g., eth-0 and usb-0).
The serial number can contain up to 24 alphanumeric characters.
4.3 Modifying the Unit Configuration via Script Files
Besides CLI, another way of modifying the unit’s current
configuration is to use the script file upload method. Unlike CLI, this
method does not require a serial port. This method is meant to be
used primarily by ISPs, as a quick and easy way to update the
configuration of their customers’ boxes.
The script file is uploaded to the unit’s IP address via ftp or tftp.
Once the script file has been uploaded to the unit, the file may be
executed immediately or at a later time, depending on the
autoupdate flag (see note below). If the autoupdate flag is set to
true, the CLI commands in the configuration file are executed
immediately. If however, the autoupdate flag is set to false, then the
CLI commands are held in RAM and are not executed until the
apply command is issued via CLI.

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Please refer to section in this document for details on CLI Scripting and Script Programming.
The autoupdate flag indicates whether configuration files will be executed immediately or only upon
issue of an apply command. For more details on the autoupdate flag and the commands related to its use, see
the CLI Reference Manual.
4.3.1 Notes on Using Script File Configuration
Important points concerning script file configuration include:
 The script file can only be used to change the
current configuration. It cannot be used to update or
replace the factory defaults file (default configuration
file) in the flash image.
 In order to modify an existing interface, it may be
necessary for the script file to delete the interface first,
and then recreate it.
 In order for the new configuration to be saved to
flash memory, the script file must contain the commands
commit and reboot.
4.4 Managing Configuration Changes
Whenever you change the unit's configuration and do a commit, the
changes are saved into the flash. Doing a reboot after a commit
reboots the unit with the latest changes. The reboot command
supports the following options.
 last: to reboot the unit using the latest saved
configuration use the reboot last command.
 backup: to reboot the unit using the configuration of the
operation that was committed before the last commit
operation, use the reboot backup command.
 Default: to reboot the unit using the default
configuration, use the reboot default command.
 Clean: to reboot the unit with zero configuration, use the
reboot clean command. This assumes that the user has a
serial port connected to the unit. This is so, because in a
clean configuration even Ethernet is not configured.
 Minimum - to reboot the unit with only the size (with all
default parameters), create ethernet intf and create
user commands executed, use the reboot minimum
command.
The Ethernet interface and the user are created with the parameters used in the default configuration. The
minimum configuration aims to configure the unit so as to allow a telnet to it from the LAN.
Note that when you reboot with a given configuration, say reboot clean, the other configurations are not
lost. To go back to the last saved configuration after you have done a reboot clean, just do a reboot last.