PVC Migration Tool

The PVC Migration Tool can be used to convert previously-configured ATM PVCs, where both ends of the connection terminate on BXM cards, to SPVCs. This appendix describes the PVC Migration Tool, which is run from the StrataView Plus workstation, and also provides instructions for using it.

This appendix contains the following sections:

Installation of the Migration Tool on the StrataView Plus Workstation

The PVC Migration Tool is packaged separately from StrataView 9.0 (or 9.1) suite and its tar file is located under the server ftp-eng.cisco.com in the following directory:

/sita1234/Release9.0LA/release9.0.04/SVplus9.0/PVC_Migration_10_01

This is an ftp server. Use anonymous ftp to download the Migration Tool tar file. After the tar file is downloaded and placed in the /usr/users/svplus directory on the StrataView Plus Workstation (Solaris 2.5 platform), perform the following steps:

Step 1 Make sure that the StrataView Plus 9.0 (or 9.1) software is installed and is working properly.

Step 2 From any xterm window, log in as a root by typing:

su root [Enter]

Password: <password> [Enter]

Step 3 Install the PVC Migration Tool by typing:

tar -xvf PVC_Migration_10_00

When the tar command is complete, the installation of PVC Migration Tool is also completed. The Migration Tool named "migrtool" will be in the /usr/users/svplus/tools directory. The files copied from the tape to this directory are:

expect
init.tcl
migrdrv.exp
migrproc.exp
migrtool
tclsh

A sample Migration Tool configuration file, migration.conf, will be copied to /usr/users/svplus/config.

Migration Tool Config File

The Migration tool takes a configuration file (named "migrtool.conf") to get the BPX 8620/ESP node name, userid, password, StrataView database name, etc. An example of a migrtool.conf file is shown as follows:

 
# name of StrataView database, default is "stratacom"
database stratacom
# number of times to retry adding SPVC connection, default is 3
retries 3
# timeout value in setting up SPVC connection, default is 5 seconds
timeout 5
# list of nodename/userid/passwd, no defaults
telnet nmsbpx01 StrataCom othello
telnet nmsbpx09 StrataCom othello
telnet nmsbpx11 StrataCom othello
telnet nmsbpx10 StrataCom othello
telnet nmsbpx08 StrataCom othello
 
Where only keywords: database/retries/timeout/telnet are currently supported,
and they can be in any order in the configuration file.  Lines beginning with
a # are comments.

PVC Migration Tool Process

The migrtool is a tool for converting ATM PVC connections into SPVC connections. It has two modes: interactive command line mode and non-interactive batch mode. Either migration mode is invoked from command line on the StrataView Plus workstation. The Interactive mode requires one endpoint identifier of the PVC as an argument. The endpoint identifier is in the form of nodename.slot.port.vpi.vci. You can use the StrataView Plus Connection Manager to view an existing PVC's connection parameters. During execution, the migration process checks that a PVC exists in the StrataView Plus database at the specified endpoint. If the PVC is not in the OK state, it asks the users whether they want to continue. There is a high probability that the migration may not succeed if the PVC connection is in a failed state. The migration process then checks the VPI range for the SVC on both the local and remote endpoints of the PVC from the database. If VPIs are not within the ranges, it will ask the user to provide new VPI ranges for the SVC, and sets the new VPI range for the given endpoints. The Migration Tool then prompts the user for VPIs and VCIs to setup the test SPVC connection. The test SPVC connection is set up to check whether the bandwidth and route are available through the network for the desired SPVC.

Once the user specifies the VPI and VCI for the test connection, the migration process will spawn an expect script to migrate the given PVC into an SPVC. The tool communicates with the BPX 8620 and ESP through telnet sessions. The tool retrieves the usernames and passwords, for initiating telnet session with the end WAN Service Nodes and their respective attached ESP shelves, from a user supplied password file (migration.conf, which was described previously). It uses these telnet sessions to send BPX 8620 and ESP CLI (command line interface) commands. If the test SPVC setup is successful, the expect script deletes the test SPVC. It then deletes the PVC connection and adds the SPVC using the original PVC endpoints and the same connection parameters. If the SPVC setup is successful, the tool asks you for the next PVC to be migrated (interactive mode), or proceeds with the migration of the next PVC connection (batch mode).

The Migration Tool exits when you type in "quit" (interactive mode). The result of the migration is displayed in the window where the Migration Tool is running. Also, a log file, migrtool.log will record all the steps performed and their results.

If there are any failures in setting up the connection, the process will backoff and try to restore the previous PVC, then it will terminate. Major operation steps and error messages during migration are printed on standard output. Detailed log and error message are recorded respectively in migrtool.log and migrtool.err under the $SVHOME/log directory.

Connection Parameter Mapping

When setting up the SPVC test connection, and thereafter, the SPVC connection, the Migration Tool uses the existing bandwidth parameters from the existing PVC connection.

Note The Migration Tool does not migrate abr.fs (that is, vbr.3 with foresight) connections. It migrates cbr.1, vbr.1, vbr.2, vbr.3, ubr.1, ubr.2 and abr.1 BXM-to-BXM PVC connections only.

Some of the connection parameters used to set up SPVC ATM connections cannot be mapped from their corresponding PVC connection parameters. These are:

retry_time: defaults to 5 seconds (can be set to other value from the migrtool.conf file)
bearer_class: 2 (for all service types and vcc connection), 3 (for all service types and vpc connection)
qos: 0 (for all service types)
conn_type: vbr_nrt (for service types vbr.1, vbr.2, vbr.3)
traffic_set: 1 (vbr.1), 2 (vbr.2), 3 (vbr.3), 4 (ubr.1), 5 (ubr.2)
max_admin_weight: 65536
rif: 12 (for service type abr)
rdf: 15 (for service type abr)
adtf: 1000 (for service type abr)
trm: 100 (for service type abr)
cdf: 3 (for service type abr)
crm: tbe/nrm(for service type abr)

All other SPVC connection parameters used to set up the SPVC ATM connection are mapped 1 to 1 from the corresponding parameters of the original PVC connection. Please refer to the section Adding an SPVC in Chapter 8 and Appendix J, SPVC Command Line Interface, for more information on SPVC connection set up, command syntax, and the connection parameter values.

Migration Plan

The process of converting previously configured ATM PVCs to SPVCs, using the Migration Tool, consists of three general steps:

1 ) All the BPX 8620 in your network should be running Release 9.1 software and the ESP shelves should be running Release 2.2 software. The network should be in OK condition.

2 ) You must identify the PVCs that are to be migrated. Use the StrataView Plus Connection Manager GUI to view the list of connections. For each of the selected PVC connections, open the Modify window to get the current route of the connection. It is likely that the migrated SPVC connection will use the same route.

3 ) You must adjust the resource partitioning (that is, the number of SVC channels and the bandwidth) on the line and trunk cards through which SPVCs are to be routed. Use the CLI for each BPX 8620 to set the resources for SVCs. SPVC connections use the same resources as SVC connections. For trunk, use the cnftrk command to setup SVC Vpi Min, SVC Channel, and SVC Bandwidth. For end point ports, use the cnfport command to setup SVC Channel, SVC Vpi Min, SVC Vpi Max, and SVC Bandwidth. Make sure that there are enough SVC resources (number of channels, bandwidth, etc.) to set up the SPVC connections. At the same time, make sure that the existing PVC connections do not go to the failed state because of inadequate resources.

This step is optional and requires you to use the BPX 8620's command line interface.

Note If there are insufficient resources for both PVCs and SPVCs, you may have to incrementally migrate PVCs to SPVCs.

4 ) On the StrataView Plus workstation where StrataView Plus 9.0 (or 9.1) is running, execute the PVC Migration Tool. The Migration tool will delete PVCs using the BPX 8620 CLI and add SPVCs with the same VPI/VCI using the ESP CLI commands. The StrataView Plus Migration Tool communicates with the BPX 8620 CLI and the ESP Configuration Interface using telnet sessions. StrataView Plus should be running when you execute the Migration Tool.

Failure Cases and Recovery

When an SPVC add fails, the Migration Tool's expect script resets the VPI range for SVCs to its previous setting and adds back the original PVC. If the original VPI range is the same as the new VPI range for SVCs at either endpoint (local/remote), the expect script will not be able to add back the PVC when the it fails to add the SPVC. This is because PVCs cannot be added within the SPVC VPI range.

In the following cases, the test SPVC may have been added successfully, but the migrated SPVC could not be added:

If the node is unreachable after test SPVC add is done.
If the card/port fails after the test SPVC add is done.
If another user may adds a connection using the same endpoints right after the PVC is deleted.
If another user changes the bandwidth and the number of SVC channels on the end nodes or via nodes.
If another user adds other SPVCs which have same endports or via nodes and these connections use up the bandwidth so that there is insufficient bandwidth left for the migrated SPVC.

For the first two cases, you can fix the problem and restore the node/trunk/card/port to active state. Then, simply add back the desired SPVC. To avoid the remaining cases, you must perform the migration process in a controlled environment, that is, no other users should be allowed to provision connections when PVCs are being migrated to SPVCs.

The Migration Tool periodically polls the ESP to discover the result of connection add after it sends adding SPVC commend to the ESP . The default poll interval is 1 minute and number of retries is 3. You can change these values in the migration.conf file. Also, the ESP will derive the NSAP address for setting up the SPVC from the given node, slot and port values.

Note In case of a race condition, that is, the provisioning of a connection using the same endpoint values from more than one CLI, the expect script will fail to add the SPVC. In this case, it will display the reason for failure reported by the node. You can examine the node's error log to find out the detailed reason for failure.

Things to Watch for During Migration

During migration of the of PVCs to SPVCs, you should be aware of the following situations:

To avoid race conditions on the BPX switch, there is a command locking mechanism for BPX switch commands. If a user is using a command that belongs to the "locking group", no other user can run any commands that belong to the "locking group" on the same node. About two-thirds of the BPX switch commands belong to the "locking group". Most of the BPX switch commands used by the Migration Tool belong to the "locking group". This implies that the failure rate will be high for PVC migration if there other users issuing commands when the Migration Tool is issuing commands to the same BPX switch.
The occurrence of some hardware or software failures after the deletion of a PVC may cause the failure of adding the SPVC and will also block the effort to add back the PVC. The reason is the time to recover from the failures are longer than the timeout time on Migration Tool. The consequence is that the migration will fail and the PVC will be removed. For example, BCC reset, BXM reset, ... etc. Under these situations, the user needs to manually add back the PVC the BPX 8620 or BXM has recovered from the failure.
The VPI range is another limitation that prevents deleted PVCs from being added back. It is possible that PVC can not be added back after the failure (to add the SPVC) because the VPI range does not allow it. To resolve this and add back the PVC, you have to change the VPI range. However, to change the VPI range, you may need to delete some SPVCs.
It is important to fully realize that no PVC within the SVC's VPI range can be added to the BPX switch. When you change the VPI range during migration, the VPI range available for PVCs is changed at the same time. Thus it is important to plan ahead the order of PVCs to be migrated.
The Migration Tool performs some checking during the adding of the SPVC test connection. If the PVC is a VPC, then the test connection has to be a VPC with different VPI. If the PVC is a VCC, then the test connection has to be a VCC with different VPI or VCI.
The success of PVC migration relies on good planing, especially the access to control of the network, the resource partitioning (trunks and ports), and the migration order (considering the VPIs).

Interactive Mode Operation

The migration process migrates one PVC connection at a time in an interactive mode. The tool will first parse the arguments (nodename.slot.port.vpi.vci), retrieve connection parameters from StrataView Plus database, prompt for new VPI ranges for the SVC if necessary, and then set the new VPI ranges. The Migration Tool will first create a test SPVC using the same endpoint configuration, but different VPI's and VCI's. The test SPVC will have connection parameters which are mapped from the PVC connection. The reason to set up the test SPVC connection is to check whether the bandwidth and the route are available to setup the desired SPVC. The test SPVC is a special type of connection which ignores the existence of CPE at the endpoints. The VPI's and VCI's used for the test SPVC should not conflict with the existing connections.

The following example illustrates a sample session of migrating a PVC to an SPVC in the Interactive Mode. In the example, the "%" is the shell prompt. The ">>" is the Migration Tool prompt requesting your input. The lines between prompts are the output messages from the tool.

				 																	Welcome to use PVC to SPVC Migration Tool (V1.0.00)
 
            Copyright: Cisco Systems Inc, 1997
    Initializing ............ ok
 
    Please enter node.slot.port.vpi.vci (use * as VPC's vci)
				 														enter "quit" or "exit" to exit migration tool
migration>> nmsbpx10.4.10.20.20
																		master endpoint is 4.1.20.20
																		slave endpoint is 5.1.21.21
    master endpoint current vpi range for svc is 0 - 10
    slave endpoint current vpi range for svc is 0 - 10
    need new master endpoint vpi range for svc (must cover vpi 20,
																		and in the range [0, 255])
migration>> enter new vpi range for svc: 0 20
																		need new slave endpoint vpi range for svc (must cover vpi 21,
																		and in the range [0, 255])
migration>> enter new vpi range for svc: 0 21
																		input test conn vpi/vci for master endpoint
    (VPI must in range [0, 20], and VCI in [32, 65535])
migration>> enter valid vpi, vci: 4 40
																		input test conn vpi/vci for slave endpoint
    (VPI must in range [0, 21], and VCI in [32, 65535])
migration>> enter valid vpi, vci: 5 50
...... migration operation performed ......
																		PVC to SPVC migration successful
    Please enter node.slot.port.vpi.vci (use * as VPC's vci)
				 														enter "quit" or "exit" to exit migration tool
migration>> quit
%

Note that for a boundary case, where both the local and remote end of the PVC to be migrated have the same node, slot, and port, the Migration Tool still prompts you to enter a new SVC range for both the master (local) and slave (remote) end of the SPVC. A single physical port cannot have two VPI ranges, however. In this case, if the user enters different new SVC VPI ranges, the Migration Tool will select a single range that includes the VPIs for both the master and slave end points of the SPVC connection. Should the Migration Tool encounter an error during the migration operation, it will display the error message captured from BPX 8620 or ESP node, and abort the migration of the current PVC.

Batch Mode Operation

The Migration Tool can be invoked in a batch mode that does not need user interaction. In the batch mode, the tool takes an input file that defines PVC connections to be migrated, together with new VPI ranges for SVCs and VPI/VCI's for test SPVC connections. The operation logs any error messages and records them in the same manner as the interactive mode. The tool exits on the first failure of a PVC connection migration, ignoring the rest PVC connections in the input file.

The Migration Tool can be started in batch mode by:

% migrtool -f <batch input file name>
where each line in the batch input file has the following format:
nodename.slot.port.vpi.vci master_min_svc master_max_svc slave_min_svc slave_max_svc master_test_vpi master_test_vci slave_test_vpi slave_test_vci

You must specify new SVC ranges for VPIs at both master and slave endpoints as well as VPI/VCIs for test connections in the input file. The Migration Tool is smart enough to discard VPIs for the new SVC range, should the current SVC range for VPIs configured at that endpoint already cover the VPI of the connection. No blank lines or comment lines are allowed in this input file.

Table of Contents

PVC Migration Tool