Options for Managing a DTC Remotely White Paper Jeff Bandle 21-January-2003
1. Overview The Datacomm Terminal Controller (DTC) product is a multi-protocol networked device used at many MPE/iX and HP-UX sites to provide networked access to the system via many different protocols (e.g. serial terminal, serial printer, Telnet access, X.25 PAD, X.25 System to system..etc). Configuration and management of the DTC can be done either through system-based utilities, such as NMMGR or DTCMGR/UX or a PC based utility that sits on top of Openview, the OpenView DTC Manager (OVDTCMGR).
connection. It was envisioned that this product would reside in the computer room, next to the CPU with a simple 10 Mbit connection running between the system and the DTC. A simple, lightweight, proprietary protocol was developed that would enable the user to make networked connections between the DTC and a serial device.
With this added complexity came the ability to have DTCs stationed at remote locations with the DTCs managed by an inexpensive PC that could be shared with other activities in the remote office. This allowed the management platform to be leveraged from existing equipment, but it also required that access be given to somebody either at the remote office or setup for dial in access in order to have control of the remote office DTCs.
3. Options 3.1. Option 1: Status Quo In this option, the user decides to continue using the OVDTCMGR platform at their remote sites. 3.1.1. Advantages In this scenario, no changes are required at all by the customer. Current configurations remain the same and the customer continues using the same tasks and processes that have already been established in order to manage the use of their DTCs. The customer’s users who connect via the DTC see no difference in their connection mechanism or ability. 3.1.2.
3.2.2. Disadvantages If the customer doesn’t have an existing HP-UX on its network, than an HP-UX system would need to be purchased, resulting in an extra cost for the customer. Also, the functionality that is supported on the HP-UX DTC management platform is a subset of what is supported in MPE/iX. Primarily, because of a different ability to make connections via X.25, the HP-UX management platform doesn’t allow the configuration of this functionality on DTCs. Customers with a need for X.
site requiring their own DTC management system, the cost factor alone would become prohibitively expensive. Also, if the site only contained DTCs connecting to HP-UX systems, than this solution would also add a steep learning curve to the additional cost factor. 3.4. Option 4: Bridge/Router Configuration In this option, the existing networking equipment used to connect the remote site to the main HP 3000 location would be configured to bridge MPE/iX DTC traffic.
This takes everything on the segments and bridges it except ip (it routes ip). Great way to find out what is on your WAN. TO LOCK IT DOWN TO ONLY THE DTC EQUIPMENT... configure terminal access-list 200 permit 0xf8f8 0x0000 access-list 200 permit 0xfcfc 0x0000 Now apply the access-list to the interface where the DTC's come into... configure terminal int eth x\x bridge-group 1 input-lsap-list 200 This turns the bridge group access-list into a filter for only the protocol type required by the DTC's.
and an upgrade may be needed. It is also possible, that the remote networking layout may be architected in a way that the DTC management traffic over the network takes too long to reach the HP 3000, causing the HP 3000 management tools to fail the management of the DTC. If this occurs, the MPE/iX lab would need to investigate and provide a patch that would address this issue.
