Figure 1 Traditional Approach to Bridging Across WAN Links
This chapter describes OpenROUTE's implementation of the Data Link Switching (DLSw) protocol. The DLSw protocol offers a wide range of functionality that enables you to integrate LAN-based SNA traffic into heterogeneous Wide Area Networks (WANs). This implementation of the DLSw protocol includes support of RFC 1795 (DLSw V1.0), handling both NetBIOS and SNA traffic.
The following sections explain how to configure your router for DLSw:
About DLSw
Setting Up DLSw
Sample DLSw Configuration 1
Sample DLSw Configuration 2
On Demand and Explicitly Configured TCP Sessions
Using DLSw Groups
Mixing PU2.0 and T2.1 Link Stations on Multipoint Lines
About DLSw
DLSw is essentially a forwarding mechanism for NetBIOS and SNA protocols over both SDLC and LLC2 data links. It relies on the Switch-to-Switch protocol (SSP) running over TCP/IP to provide a reliable transport of SNA traffic over the internet. DLSw does not provide full routing capabilities. Instead, it works by providing switching at the data link layer. Rather than bridging LLC2 frames, DLSw terminates the LLC2 connection locally and encapsulates only the Information (I) and Unnumbered Information (UI) frames in TCP frames. The router ships the TCP frames over the WAN link to a neighbor DLSw router for delivery to their intended end station addresses.
How DLSw Works
LLC2 and SDLC are connection-oriented protocols. DLSw gives these protocols the dynamic characteristics of routable protocols. Equally important, DLSw preserves the end-to-end reliability and control features that make LLC2 and SDLC effective for communication.
Problems Inherent in the Bridging Solution
Figure 1 illustrates the traditional approach to bridging LLC2 frames across WAN links. The problem with this approach is that network delays occur much more frequently in the WAN than on a LAN. Such delays can arise from simple network congestion, slower line speeds, or other factors. Each of these factors increases the possibility of a session timing out and of data failing to arrive at the destination.
In addition, LAN protocols like LLC2 use much shorter retransmit/response times than those designed for use in the WAN. This makes maintaining end-to-end connections across WAN links extremely difficult, causing session timeouts to occur.
The frequency of session timeouts is not the only problem. Another problem arises when data is delayed while crossing the WAN. When a sending station retransmits data that is not lost, but delayed, LLC2 end stations may end up receiving duplicate data. While this would seem to safeguard the data, it can lead to confusion of the LLC2 procedures on the receiving side. This may, in turn, lead to inefficient use of the WAN link.
Figure 1 Traditional Approach to Bridging Across WAN Links
Protocol Spoofing
To reduce the chance of session timeouts and to maintain the appearance of end-to-end connectivity for sending stations, DLSw works by terminating or spoofing LLC2 connections at the local router. When terminating the connection, the local router sends acknowledgments to the sending station. The acknowledgment tells the sender that data previously transmitted have been received, and prevents the station from retransmitting.
From this point forward, assuring that data gets through is the responsibility of the DLSw software. The software accomplishes this by encapsulating the data in routable IP frames, then transporting them (via TCP) to a DLSw peer. The neighbor DLSw router strips away the frame headers, determines the address of the data's intended recipient, and establishes a new LLC2 connection with that end station. Figure 2 illustrates this relationship between two DLSw neighbor routers.
Figure 2 Data Link Switching Over the Wide Area Network
SDLC Data Link Support
In addition to LAN data link support for SNA (LLC2) and NetBIOS, DLSw supports SDLC data link termination for SDLC-attached SNA devices. You can configure the router to act in either a primary or a secondary local link role. Support for SNA data link type is independent of the corresponding neighbor DLSw router; that is, the local router can have SDLC devices attached and the remote router's SNA devices can be on a Token Ring (LLC2).
Figure 3 SDLC Support
Primary and Secondary Link Roles
In Figure 3, if the DLSw router is in the primary link role, the router polls downstream SNA PU2.0 or T2.1 devices such as IBM 3174 cluster controllers or the AS/400, respectively. If the router is in the secondary link role, the adjacent (primary) station polls the router. An example of a local secondary link configuration is where the SDLC link connects the router to a Front End Processor (FEP), such as 3745. Another example is where the router is SDLC-attached to a T2.1/APPN device, such as an AS/400, and the T2.1 device acts as a primary link station.
You can configure the type of SNA node (PU2 or T2.1) for each SDLC link station. In addition to the link role consideration, the router uses the node type to determine whether or not to forward XID frames to the adjacent physical device.
For example, a local station configured with a PU2 node type on a local primary link does not forward NXID frames it receives to the actual attached device. Instead, the router generates the appropriate XID0 response using the configured IDNUM and IDBLK values directly. This feature isolates the actual physical device configuration from the IBM host's configuration parameters, and permits, for example, transparent substitution of a remote SDLC device for an existing local Token Ring configuration.
With T2.1 SDLC devices, on the other hand, the router explicitly forwards all XID frames end-to-end, allowing XID3 parameter negotiation support. Mixed node types may be supported on a single multidrop physical link.
Both SDLC link role configurations support multiple adjacent link stations (devices) on one physical link. In the case of SDLC secondary, you can configure the router for multiple stations, as one of several stations on the physical line, or both.
Negotiable Link Role
In addition, you can configure SDLC link role as negotiable. In Figure 3, the router allows SDLC XID frames to flow in both directions until the router determines the role of its adjacent link station, after which the local role dynamically resolves to the appropriate value. This feature is intended to primarily support end-to-end T2.1/APPN traffic, where the respective end station resolves its role dynamically, using XID3 frames. The router does not support dynamic role negotiation on multipoint links or dynamic T2.1 link station address resolution.
If you configure respective SNA T2.1 end stations for role negotiation, but configure the router with a non-negotiable link role (the role is primary or secondary), the router attempts to "bias" the role negotiation protocol such that the local link station role is resolved accordingly.
Group Poll Feature
In addition to the SDLC link role flexibility that DLSw offers, the router also supports the Group Poll (IBM GP3174) feature when you configure the router for local secondary multipoint, since the adjacent primary link station, typically an IBM mainframe, need only issue a single unnumbered poll to simultaneously address all stations suitably configured on the router.
Benefits of DLSw
Because DLSw terminates the LLC connection at the local router, it is especially effective at eliminating SNA session timeouts and reducing WAN overhead on shared circuits. The protocol has these main benefits:
Reduces the possibility of session timeouts by terminating LLC2, NetBIOS, and SDLC traffic at the local LAN.
Reduces WAN network overhead by eliminating the need to transmit Receive Ready (RR) acknowledgments over the WAN. DLSw confines the RRs to the LANs that are local to each DLSw router.
Provides flow and congestion control and broadcast control of search packets between DLSw routers and their attached end stations.
Increases Source Route Bridging (SRB) hop-count limits.
Allows protocol conversion from LLC2 to SDLC.
Supports NetBIOS traffic.
Configuration Requirements
Configuring Adaptive Source Route Bridging (ASRT) for DLSw, as needed.
Configuring IP for DLSw
Configuring SDLC Interfaces
Configuring DLSw
Configuration Requirements
OpenROUTE supports DLSw over IEEE 802.5 Token Ring, SDLC, Ethernet, and FDDI. To use DLSw, you must perform the following actions:
Configure ASRT, as needed
Configure IP
Configure OSPF and MOSPF, as needed
Configure SDLC devices, as needed
Configure DLSw
For Token Ring interfaces:
Enter disable transparent to disable transparent bridging. Then, enter enable source routing to turn on source routing for the bridge port. You will be prompted for an SRB segment number.
For Ethernet or FDDI interfaces:
Enter enable transparent to enable transparent bridging on the bridge port.
To create a SAP filter,
Enter add protocol-filter dsap 4 at the Bridge config> prompt.
Specify the bridge port to which the filter applies. The command tells the router to filter all traffic that has a DSAP of 4 on a designated port. (Note that this assumes you have chosen a SAP of 4 for DLSw traffic. Assigning a SAP is something you do during the DLSw configuration.)
If you do not define static routes between DLSw neighbors, you must choose either OSPF or RIP as your routing protocol. Using OSPF is recommended, because it entails less network overhead than RIP.
To enable OSPF, enter protocol ospf at the Config> prompt. This brings you to the OSPF Config> prompt. To use DLSw group functionality, enable Multicast OSPF.
For more information on using OSPF, see OSPF in the Online Library.
To enable RIP, enter enable rip at the IP Config> prompt.
Note: If you are using RIP, the router's internal IP address must match the IP address assigned to a hardware interface.
The following defaults for SDLC stations are not satisfactory:
-Maximum BTU is maximum allowable by interface
-Tx and Rx Windows are 7 for MOD 8, 127 for MOD 128
The SNA devices on the link are of mixed node types.
You want to use the group poll feature.
You want greater flexibility and control by using the SDLC monitoring commands.
If you do not explicitly add SLDC stations, the router assumes the following:
The attached stations are of type PU2 if the router's link role is primary or secondary.
The attached stations are of type T2.1 if the router's link role is negotiable.
Specify secondary if the SDLC link is connected to an adjacent SDLC primary device, such as a FEP.
Specify negotiable if a T2.1 (APPN) device is attached and you anticipate XID3 exchange.
Connecting multiple T2.1 devices on a multidrop link by definition denotes that true link role negotiation is not being performed, and you should use a predefined link role on both the router and the T2.1 device(s).
It is not required that the respective T2.1 devices perform true end-to-end role negotiation when you configure the router's link as negotiable; the router senses the actual role, whether predetermined or not, and adjusts accordingly. Conversely, if you anticipate end-to-end T2.1 role negotiation and do not configure the router's link role as negotiable, the value you configure influences the role negotiation.
The router supports group polling only when the local link role negotiates to secondary. It also requires a corresponding configuration on the adjacent SDLC primary side of the link. This is typically an IBM mainframe running IBM's Network Control Program (NCP) software; if so, use the GP3174 keyword on the PU definition statement to designate group polling.
This segment number should be the same for all DLSw routers, and unique in the SRB domain. The bridge uses this number in the Routing Information Field (RIF) when the router sends the frames on the LAN. The segment number is the key to preventing loops.
You do not need to open SAPs in a pure DLSw/SDLC router configuration.
Note: If you enable SAP List Filtering, you must open SAPs on the target DLSw router.
Note: A router can participate in a group only if its neighbor router is a platform based on OpenROUTE running DLSw. If you configure one DLSw router for a group, you must enable OSPF and MOSPF on all DLSw routers in the group.
Adding SDLC link stations requires knowledge of the device link station address, the optional NodeID field information (IDNUM and IDBLK), and the source and destination MAC addresses and SAPs for mapping to the corresponding remote SNA device.
The link station address is required, and must match the address of the actual physical device you are connecting.
See the add sdlc command for more information.
The internal IP addresses of R1 and R2.
The IP address of each port used to maintain the TCP connection between the routers.
The interface numbers assigned to the Token Ring and SDLC devices and used for the TCP connection.
The source route bridge segment number of the attached Token Ring.
Adding Physical Devices
If your router platform requires you to add devices, add one Token Ring and two serial devices. For example:
After adding devices, you can list the devices to verify that you have assigned them to the appropriate router interfaces.Config>add device token ring
Device Slot # (0-2) [0]?
Adding device as interface 0
Config>add device quad-serial
Device Slot # (0-2) [1]?
Adding device as interface 1
Config>add device quad-serial
Device Slot # (0-2) [2]?
Adding device as interface 2
Note: The format of this information differs depending on the router platform.Config>list device
Token Ring: CSR 80000000, vector 68
Ethernet1 (SCC Ethernet): CSR 81600, CSR2 80C00, vector 94
WAN1 (SCC Serial Line): CSR 81620, CSR2 80D00, vector 93
Config>network 0
Token-Ring interface configurationTKR config>speed 16
TKR config>media stpTKR config>list
Token-Ring configuration:Packet size (INFO field): 2052
Speed: 16 Mb/sec
Media: Shielded
RIF Aging Timer: 120
Source Routing: Enabled
MAC Address: 000000000000
IPX interface configuration record missingTKR config>exit
If necessary, use the set hdlc commands to change any of these defaults. Note: For RBX Series platforms, you must set the cable type using the set cable command.Config>network 1
Circuit Configuration
Circuit Config <NET-1> sl
Serial Line ConfigurationSerial Config <WAN1> list
Line Discipline: SyncMaximum network layer frame size: 2048
Speed: 2048000
HDLC Data encoding: NRZ
HDLC Idle State: Flag
Transmit delay counter: 0 units
Cable: V.35 DCE
Synchronous clocking: Internal
SLC Config>exit
Config>set data-link sdlc
Interface Number [0]? 2
Config>network 2
SDLC user configuration
Creating a default configuration for this link
SDLC 2 Config>
SDLC 2 Config>add station
Enter station address (in hex) [C2]?
Enter station name [SDLC_C2]?
Include station in group poll list ([Yes] or No):
Enter max packet size [2048]?
Enter receive window [7]?
Enter transmit window [7]?
Enter PU2 or T2.1 node type [PU2]?
If any SDLC link settings do not apply to the link role, the software ignores them. You can change any of these settings using the SDLC configuration commands described in Configuring and Monitoring SDLC Interfaces.SDLC 2 Config>list link
Link configuration for: LINK_2 (ENABLED)
Role: PRIMARY Type: POINT-TO-POINT
Duplex: FULL Modulo: 8
Idle state: FLAG Encoding: NRZ
Clocking: EXTERNAL Frame Size: 2048
Speed: 0 Group Poll: 00
Cable: V.36 DTE
Timers: XID/TEST response: 2.0 sec
SNRM response: 2.0 sec
Poll response: 0.5 sec
Inter-poll delay: 0.2 sec
RTS hold delay: DISABLED
Inter-frame delay: DISABLED
Inactivity timeout: 30.0 sec
Counters: XID/TEST retry: 4
SNRM retry: 6
Poll retry: 10
For RBX Series routers, you must set the cable type. For example:
SDLC 2 config>set cable rs-232 dte
Config>protocol ip
Internet protocol user configuration
IP config>add address
Which net is this address for [0]? 1
New address [0.0.0.0]? 128.185.236.33
Address mask [255.255.0.0]? 255.255.255.0
Enter list to display the newly added information.IP config>set internal-ip-address 128.185.236.49
IP config>list all
Interface addresses
IP addresses for each interface:
intf 1 128.185.236.33 255.255.255.0 Network broadcast, fill 0
Internal IP address: 128.185.236.49Routing Protocols
BOOTP forwarding: disabled
Directed broadcasts: enabled
ARP Subnet routing: disabled
RFC925 routing: disabled
OSPF: enabled
Per-packet-multipath: disabled
RIP: disabled
IP config>exit
Config>protocol ospf
Open SPF-Based Routing Protocol configuration console
OSPF Config>list all
--Global configuration--
OSPF Protocol: Disabled
External comparison: Type 2
AS boundary capability: Disabled
Multicast forwarding: Disabled
--Area configuration--
Area ID AuType Stub? Default-cost Import-summaries?
0.0.0.0 0=None No N/A N/A
OSPF Config>enable ospf
Estimated # external routes [0]? 100
Estimated # OSPF routers [0]? 25
OSPF Config>enable multicast
Inter-area multicasting enabled? [No]: N
OSPF Config>set interface 128.185.236.33
Attaches to area [0.0.0.0]?
Retransmission Interval (in seconds) [5]?
Transmission Delay (in seconds) [1]?
Router Priority [1]?
Hello Interval (in seconds) [10]?
Dead Router Interval (in seconds) [40]?
Type Of Service 0 cost [1]?
Authentication Key []?
Retype Auth. Key []?
Forward multicast datagrams? [Yes]:
Forward as data-link unicasts? [No]:
IGMP polling interval (in seconds) [60]?
IGMP timeout (in seconds) [180]?
OSPF Config>
OSPF Config>list all
--Global configuration--
OSPF Protocol: Enabled
# AS ext. routes: 100
Estimated # routers: 25
External comparison: Type 2
AS boundary capability: Disabled
Multicast forwarding: Enabled
Inter-area multicast: Disabled
--Area configuration--
Area ID AuType Stub? Default-cost Import-summaries?
0.0.0.0 0=None No N/A N/A
--Interface configuration--
IP address Area Cost Rtrns TrnsDly Pri Hello Dead
128.185.236.33 0.0.0.0 1 5 1 1 10 40
Multicast parameters
IP address MCForward DLUnicast IGMPPoll IGMPtimeout
128.185.236.33 On Off 60 180OSPF Config>exit
Config>protocol bridge
Adaptive Source Routing Transparent Bridge user configuration
Bridge config>enable bridge
Begin by disabling transparent bridging on the Token Ring port. Port number one is port 1 on interface 0. In other words, port 1 is the logical bridge port for the physical interface set up for the Token Ring (see Figure 4).Bridge config>list port
Port Id (dec) : 128: 1, (hex): 80-01
Port State : Enabled
STP Participation: Enabled
Port Supports : Transparent Bridging Only
Assoc Interface : 0
Path Cost : 0
+++++++++++++++++++++++++++++++++++++++++++
Bridge config>dis transparent
Port Number [1]?
Bridge config>
Bridge config>enable source
Port Number [1]?
After assigning a segment number, enable DLSw for the bridge.Segment Number for the port in hex(1 - FFF) [1]? b0b
Bridge number in hex (1 - 9, A - F) [1]?
Listing the bridge configuration confirms that you have configured bridging correctly.Bridge config>enable dls
Bridge config>list bridge
Source Routing Transparent Bridge Configuration
================================================
Bridge Enabled Bridge Behaviour: Unknown
+----------------------------+
-------------------| SOURCE ROUTING INFORMATION |------------------
+----------------------------+
Bridge Number: 01 Segments: 1
Max ARE Hop Cnt: 14 Max STE Hop cnt: 14
1:N SRB: Not Active Internal Segment: 0x000
LF-bit interpret: Extended
+-------------------+
-------------------| SR-TB INFORMATION |-------------------------------
+-------------------+
SR-TB Conversion: Disabled TB-Virtual Segment: 0x000 MTU of TB-Domain: 0
+------------------------------------+
-------------------| SPANNING TREE PROTOCOL INFORMATION |--------------
+------------------------------------+
Bridge Address: Default Bridge Priority: 32768/0x8000
STP Participation: IEEE802.1d
+-------------------------+
-------------------| TRANSLATION INFORMATION |-------------------------
+-------------------------+
FA<=>GA Conversion: Enabled UB-Encapsulation: Disabled
DLS for the bridge: Enabled
+------------------+
-------------------| PORT INFORMATION |--------------------------------
+------------------+
Number of ports added: 1
Port: 1 Interface: 0 Behaviour: SRB Only STP: Enabled
Once the filtering you need is in place, exit the bridging configuration module.Bridge config>add prot-filter dsap 4
Filter packets arriving on all ports?(Yes or [No]): yesBridge config>list prot-f dsap
Protocol Class: DSAP
Protocol Type : 04
Protocol State: FILTERED
Port Map : 1
==========================
No ETHER type Filter Records Associated
No SNAP Filter Records Associated
Bridge config>exit
Enable DLSw and set the SRB segment number. The segment number is the virtual segment number that identifies DLSw in the RIF of all LLC frames.Config>protocol dls
DLSw protocol user configuration
DLSw config>list dlsDLSw is ENABLED
LLC2 send Disconnect is ENABLED
Automatic TCP connection ALWAYS CONNECT
SRB Segment number 000
MAC <-> IP mapping cache size 128
Max DLSw sessions 1000
DLSw global memory allotment 141056
LLC per-session memory allotment 8192
SDLC per-session memory allotment 4096
NetBIOS UI-frame memory allotment 40960
Database age timer 1200 seconds
Max wait timer for ICANREACH 20 seconds
Wait timer for LLC test response 15 seconds
Wait timer for SDLC test response 15 seconds
Join Group Interval 900 seconds
Neighbor priority wait timer 2.0 seconds
DLSw config>enable dls
DLSw config>set srb 020
DLSw config>join
Group ID (1-64 Decimal) [1]?
Client/Server or neighbor Group member (C/S/P)- [C]?
Transmit Buffer Size (Decimal) [5120]?
Receive Buffer Size (Decimal) [5120]?
Maximum Segment Size (Decimal) [1024]?
Enable/Disable Keepalive (E/D)- [D]?
Neighbor Priority (H/M/L) [M]?DLSw config>list group
Group Role Xmit Bufsize Rcv Bufsize Max Segsize Keepalive Priority
1 CLIENT 5120 5120 1024 DISABLED MEDIUM
DLSw config>add tcp
Enter the DLSw neighbor IP Address [0.0.0.0]? 128.185.122.234
Transmit Buffer Size (Decimal) [5120]?
Receive Buffer Size (Decimal) [5120]?
Maximum Segment Size (Decimal) [1024]?
Enable/Disable Keepalive? (E/D) - [D]?
Neighbor Priority (H/M/L) [M]?DLSw>list tcp
Neighbor Xmit Bufsize Rcv Bufsize Max Segsize Keepalive Priority
-------- ------------ ----------- ----------- --------- --------
128.184.122.234 5120 5120 1024 DISABLED MEDIUM
You must assign a unique source MAC address to each SDLC link station. For PU2 SDLC devices, the values configured for Idnum and Idblk must match those configured for this PU in the machine with which the SDLC device wants to establish a connection.DLSw config>add sdlc
Interface # [0]? 2
SDLC Address [C1]?
Source MAC Address [000000000000]? 4000003174d1
Idblk in Hex (0-0xfff) [0]?
Idnum in Hex (0-0xfffff) [0]?
LLC Source SAP (0 for auto-assign) [0]?
LLC Destination SAP [4]?
Destination MAC Address [000000000000]? 400000000002DLSw config>list sdlc all
Net Addr Status Idblk Idnum Source SAP/MAC Dest SAP/MAC
4 C1 Enabled 017 A0021 00 40000003174d1 04 40000000002
Following is the DLSw display after configuring.DLSw config>open-sap
Interface # [0]?
Enter SAP in hex (range 0-F4), 'SNA', 'NB' or 'LNM' [4]? sna
SAPs 0 4 8 C opened on interface 0
When you have finished configuring DLSw, exit the DLSw configuration environment and restart the router.DLSw config>list dls
DLSw is ENABLED
LLC2 send Disconnect is ENABLED
Automatic TCP connection ALWAYS CONNECT
SRB Segment number 0030
MAC <-> IP mapping cache size 128
Max DLSw sessions 3000
DLSw global memory allotment 60000
LLC per-session memory allotment 8192
SDLC per-session memory allotment 4096
NetBIOS UI-frame memory allotment 40960
Database age timer 1200 seconds
Max wait timer for ICANREACH 20 seconds
Wait timer for LLC test response 15 seconds
Wait timer for SDLC test response 15 seconds
Join Group Interval 900 seconds
Neighbor priority wait timer 2.0 seconds
DLSw config>exit
Config>restart
Are you sure you want to restart the gateway? (Yes or [No]): yes
Figure 5 Sample DLSw Configuration using Primary and Secondary SDLC Stations
Notice that the Destination SAP (DSAP) on the SDLC local primary router (R1) is 0 (zero), which puts the station in passive mode and prevents the primary router from attempting to establish a session. The DSAP on the secondary router is not set to zero, allowing that router to initiate sessions. Because the FEP must poll the secondary router before the router can engage in session establishment, if the primary router attempts to establish a session and the secondary router is not being polled by the FEP, the attempt fails. Therefore, configuring the primary and secondary stations so that only the secondary router establishes sessions can avoid delays in establishing sessions. See the add sdlc command for more information on configuring DSAPs.
Configuring Router R1
On Router R1, the primary SDLC router, you need to
SDLC 2 Config>set link type multipoint
DLSw config>add sdlc
Interface # [0]? 2
SDLC Address [C1]?
Source MAC Address [000000000000]? 401AAB9200C1
Idblk in Hex (0-0xfff) [0]?
Idnum in Hex (0-0xfffff) [0]?
LLC Source SAP (0 for auto-assign) [0]? 04
LLC Destination SAP [4]? 0
Destination MAC Address [000000000000]? 0000C91202C1DLSw config>add sdlc
Interface # [0]? 2
SDLC Address [C1]?
Source MAC Address [000000000000]? 400000317582
Idblk in Hex (0-0xfff) [0]?
Idnum in Hex (0-0xfffff) [0]?
LLC Source SAP (0 for auto-assign) [0]? 04
LLC Destination SAP [4]? 0
Destination MAC Address [000000000000]? 400000000002
SDLC 1 Config>set link role secondary
DLSw config>add sdlc
Interface # [0]? 1
SDLC Address [C1]?
Source MAC Address [000000000000]? 0000C91202C1
Idblk in Hex (0-0xfff) [0]?
Idnum in Hex (0-0xfffff) [0]?
LLC Source SAP (0 for auto-assign) [0]? 04
LLC Destination SAP [4]?
Destination MAC Address [000000000000]? 401AAB9200C1DLSw config>add sdlc
Interface # [0]? 1
SDLC Address [C1]?
Source MAC Address [000000000000]? 400000000002
Idblk in Hex (0-0xfff) [0]?
Idnum in Hex (0-0xfffff) [0]?
LLC Source SAP (0 for auto-assign) [0]? 04
LLC Destination SAP [4]?
Destination MAC Address [000000000000]? 400000317582
enable auto-tcp-reconnect
disable auto-tcp-reconnect
Assign OSPF Addresses to Hardware Interfaces
Begin by entering protocol ospf at the Config> prompt to enter the OSPF configuration module. Enter set interface to assign the OSPF address to the hardware interface you are using to connect to the other DLSw neighbor.
Issue the DLSw Join-Group Command
At the DLSw config> prompt, enter join-group. The router prompts you for a group number, transmit and receive buffer sizes, type of membership in the group, and the neighbor priority for the group.
DLSw config>join-group
Group ID (1-64 Decimal) [1]? 4
Client/Server or neighbor Group member (C/S/P)- [C]?
Transmit Buffer Size (Decimal) [5120]?
Receive Buffer Size (Decimal) [5120]?
Maximum Segment Size (Decimal) [1024]?
Enable/Disable Keepalive (E/D)- [D]?
Neighbor Priority (H/M/L) [M]?
DLSw config>
OSPF Config>enable ospf
Estimated # external routes [0]? 100
Estimated # OSPF routers [0]? 25
OSPF Config>enable multicast
Inter-area multicasting enabled? [No]:
OSPF Config>
|
MaxBTU
| The maximum allowed by the interface |
|
Receive Window
| 7 for MOD 8, 127 for MOD 128 |
|
Transmit Window
| 7 for MOD 8, 127 for MOD 128 |
|
Role
| Primary |