The 3174-Peer Bridge Profile panel allows you to specify parameters to be used by the internal bridge function. These parameters include:
• The internal bridge number
• The internal ring segment number
• The external token-ring network segment number
• The number of hops over which a broadcast frame can cross
• Whether frames will be forwarded by the bridge
• Setting threshold for bridge congestion
• How long to wait before logging a bridge congestion
• How long to wait before sending an alert about a congested bridge
Chapter 4. Scenario 1: TCP/IP Using 3174 Peer Communication Only 113
---.-_ _ 3174-Peer Bridge Profile _ _ _
Token-Ring Segment Number 3174-Peer Segment Number Token-Ring Hop Count Frame Forwarding Active Bridge Performance Threshold
(Frames Discarded Per 18,(88) Logging Interval
Alert Threshold
PF: 3=Quit 4=Default 7=Back 8= Fwd
Figure 111. 3174-Peer Bridge Parameters
Question 670: Bridge Number
Question 671: Token-Ring Segment Number
The response assigns a number to the external (real) token-ring network segment. The valid range of response is a hexadecimal value from 001 to FFF, with no default. It is required for source routing.
If the 3174 is attached to an eXisting token-ring network, you should use the segment number already assigned to the token-ring network for question 671.
If an IBM Token-Ring Network Bridge Program station is active on the token-ring network; you must use the segment number assigned by the Bridge Program for question 671. If the numbers do not match, the 3174-Peer bridge will not be able to communicate on the token-ring network.
If there is more than one 3174-Peer segment on the same token-ring network, the token-ring network segment number must be the same for all the 3174-Peer segments (obviously, since they are attached to the same token-ring network).
The token-ring network segment number, however, cannot be the same as the 3174-Peer segment number.
Question 672: 3174-Peer Segment Number
The response assigns a number to the internal ring segment (the 3174-Peer segment). The valid range of response is a hexadecimal value from 001 to FFF, with no default.
If there is more than one 3174-Peer segment on the same token-ring network,
It must also be different from the token-ring network segment number. If the tOken-ring network is bridged to other token-ring networks, you must ensure that all 3174-Peer segment numbers are unique throughout the entire network.
Question 673: Token-Ring Hop Count
The response specifies the maximum number of bridges that a broadcast frame can cross. The valid range of response is a from 1 to 7, with 7 as the default.
Note that the 3174-Peer bridge is counted as one hop when frames cross from the 3174-Peer segment to the external token-ring network or vice versa.
Question 674: Frame Forwarding Active
The response indicates whether the 3174-Peer bridge is to forward frames it receives. Valid responses are:
Y = Yes (default response) N=No
W=Wrap mode Enter:
• Y if you want the 3174-Peer bridge to forward frames as well as process frames received from the tOken-ring network, or if a wrap plug is used on the Token-Ring Adapter in the 3174.
• N if you do not want the 3174-Peer bridge to forward frames received from the token-ring network. In fact, it will discard any frames it receives and stop incrementing the discard frame counters.
• W if a token-ring adapter cable is connected to the Token-Ring Adapter in the 3174 but not to the tOken-ring network (that is, not plugged into, for example, an 8230 Controlled Access Unit) and you want the adapter to open in wrap mode. Wrap mode allows 3174-Peer devices to access the 3174 token-ring gateway function for host communication without requiring the 3174 to be physically connected to a token-ring.
Note:
Before Configuration Support-C Release 3, you could put the 3174 into wrap mode by doing one of the following (depending on the
microcode level):
Install a wrap plug (PN 6165899) instead of the Token-Ring Adapter cable at the 3174 Token-Ring Adapter port; respond to question 674 with a Y.
Install a Token-Ring Adapter cable at the 3174 Token-Ring Adapter port and apply patch TR 824501 (3174 Peer Communication Wrap Mode); respond to question 674 with a Y.
Note: Patch TR 824501 is only valid for the Peer Communications RPQ 8Q0718 (Configuration Support-B Release 4). This patch is not needed for Configuration Support-C Release 1 and later because Online Test /9,10 support for wrap mode was added.
Install a Token-Ring Adapter cable at the 3174 Token-Ring Adapter port; use Online Test /9,10 to set the Frame Forwarding Active response to W.
Chapter 4. Scenario 1: TCP/IP Using 3174 Peer Communication Only 115
With Configuration Support-C Release 3, you could put the 3174 into wrap mode by dOing one of the following:
Install a wrap plug (PN 6165899) instead of the Token-Ring Adapter cable at the 3174 Token-Ring Adapter port; respond to question 674 with a Y.
Install a Token-Ring Adapter cable at the 3174 Token-Ring Adapter port; respond to question 674 with a W (Wrap).
Install a Token-Ring Adapter cable at the 3174 Token-Ring Adapter port; use Online Test /9,10 to set the Frame Forwarding Active response to W.
Configuration Support-C Release 3 allows you to set the wrap mode through customization instead of using Online Test /9,10. The token-ring adapter is still required.
Question 675: Bridge Performance Threshold
The response specifies the maximum percentage of information frames that may be discarded by the internal bridge within a one-minute interval before a count is incremented. The valid range is from 0000 to 9999; the number is in hundredths of a percent or the number of frames per 10,000. The default is 0010 and means that the discard counter will be incremented by one if 0.1010 (10 hundredths of a percent) of the frames received within anyone-minute interval are discarded. It is the same as saying the discard counter will be incremented by one if 10 out of every 10,000 frames received within anyone-minute interval are discarded.
A separate count is maintained for frames received from the token-ring network and frames received from the 3174-Peer segment.
Question 676: Logging Interval
When the internal bridge performance threshold is exceeded at the end of a one-minute interval, the bridge is congested. To measure how serious the congestion is, you can specify a time interval during which the congestion is monitored.
The monitoring begins at the end of the one-minute interval when the congestion occurred, counting that one-minute interval as the first minute of the monitoring interval. At the end of the monitoring interval, the Log Manager is invoked to record the number of minutes in that interval during which the bridge was congested. The number of minutes and a non-alertable status code are recorded in the event log. This information is time stamped.
Question 676 allows you to set the monitoring interval. The valid range of response is from 00 Hours 00 Minutes to 99 Hours 59 Minutes, with the default being 02 00 (every two hours). If 00 Hours 00 Minutes is specified, then no logging of the bridge congestion is invoked. If you specify any interval other than 0000, then logging begins only after bridge congestion has been detected.
Question 677: Alert Threshold
Within the monitoring interval set by Question 676, you can set another threshold to raise an alert if the congestion is serious. Question 677 allows you to set this alert threshold. The valid range of response is from 000 to 255, with the default being 010 minutes.
Using the default logging interval (0200) and default alert threshold (010) as an example, if bridge congestion is detected then monitoring begins. If bridge congestion total time is less than 10 minutes (the alert threshold), no alert is raised and logging is invoked at the end of two hours.
As soon as bridge congestion total time reaches 10 minutes (the alert threshold), an alert is raised, the Log Manager is immediately invoked to record a status code and the alert threshold in the event log and the logging interval is treated as if it has completed.
4.11.8 LAN Manager Profile
The LAN Manager Profile panel allows you to specify a password for each reporting link. The following rules apply to the reporting link passwords:
• The passwords need not be unique.
• Each password must be six to eight characters in length.
• Each character must be in the range 0-9 and A-Z.
• No blanks preceding or imbedded in the password are allowed
• The default is all blanks (no password specified).
The following questions allow you to specify the passwords:
• Question 690: Reporting Link 0 Password
• Question 691: Reporting Link 1 Password
• Question 692: Reporting Link 2 Password
• Question 693: Reporting Link 3 Password
Chapter 4. Scenario 1: TCP/IP Using 3174 Peer Communication Only 117
4.12· Display 3174-Peer StatlJs
Di sp lay 3174-Peer Status .:. HG 26 ---Current Functi ona 1 Group Di scarded Devi ce Port Address
88
Address Address Frame Ctr Status 81
82 83 84
85 4888 3174 2992 ••••
86 4888 3174 4992 ••••
86 87 8S 89 H) 11 12 13 14 15
To go di rectly to other tests. enter: /Test. Opti on Se 1 ect Test; press ENTER ===>
PF: 3=Qui t 5=Refresh S=Fwd 9=Ctr->8 12=Test Menu
Figure 112. Display 3174-Peer Status
D
The 1 means the interface is enabled8
HI
8 1·
For detailed information about Online Test Status Information see Chapter 5 in the Customer Problem Determination Guide, , GA23-0217.
Chapter 5. Scenario 2: Concurrent Access to SNA and TCP/IP Hosts
This scenario shows the concurrent ability of the:
• RISC System/6000 workstation to access the 3270 SNA host, using the 3174-12L as the SNA gateway.
• The 3270 terminal to access the 3270 SNA host, using the 3174-12L as a cluster controller.
• The same 3270 terminal to access the RISC System/6000, using the 3174-12L as the TCP/IP TELNET client.
The 3174-12L is attached to the S/390 host via an ESCON channel connection.
5.1 Scenario 2 Configuration Diagram
3270 SNA Host
317412L
Gateway
9.67.38.87
3270
Figure 113. 3174 MLT Access to SNA 3270 and TCP/IP Hosts
© Copyright IBM Corp. 1994
9.67.38.73
119
5.2 Scenario 2 Configuration Description
The composite network has the following components:
• An S/390 host with VTAM* V4.1
• A 3174-12L Establishment Controller with:
- An ESCON connection
Token-ring address of 400031740004
• A RISC System/6000
- Token-ring address of 100054AF58CE
• 3270 terminal