How to Configure ATM Permanent Virtual Circuits
About this document
IBM-supported ATM adapters
AIX ATM support
Configuring permanent virtual circuits
This document covers software requirements and configuration of
ATM permanent virtual circuits (PVCs) on AIX Versions 4.1.4, 4.1.5,
4.2.0, 4.2.1, and 4.3.x.
Current adapters supported by IBM are as follows:
ATM support at AIX Versions 4.x is installed via the
following filesets on the base operating system install media.
MCA Turboways 155 ATM software (4.1.x, 4.2.x, and 4.3.x):
MCA Turboways 155 ATM UTP/STP software (4.1.5, and 4.2.x):
MCA Turboways 100 ATM software:
PCI Turboways 25 STM UTP/STP software (4.2.1 and 4.3.x):
PCI Turboways 155 ATM software (4.1.5, 4.2.1, and 4.3.x):
PCI Turboways 155 ATM UTP/STP software (4.1.5, 4.2.1, and 4.3.x):
ATM is not supported at AIX Versions 4.1.1 through 4.1.3.
At AIX levels AIX 4.1.x, common ATM device driver software
is contained in the devices.mca.8f7f.com fileset. This
fileset needs to be at the latest level regardless of the
ATM adapter (MCA or PCI) you have installed.
At AIX 4.2.x and later, common ATM device driver software is
contained in the fileset devices.common.IBM.atm.rte.
PVCs can be configured in a back-to-back ATM network between
two systems, or as a point-to-point connection to a switch.
It is extremely important in a back-to-back ATM 155 Mbs
network that one node provide sonet clocking. This is not
an issue in an ATM 100 Mbs network. To provide sonet
NOTE: It is only necessary to do this on one node of the
back-to-back ATM 155 Mbs network.
- Enter smit chg_atm.
- Select the ATM adapter that is being configured in a
- At the bottom of the SMIT screen, set Provide SONET
clock to 1.
If you get a device busy message, make sure all ATM IP
interfaces are detached or removed and ATM LAN emulation
clients are defined or removed.
The first step is to configure the IP interface for the PVC.
NOTE: Alternatively, you may change Automatically
Discover Destination IP Address to no and set
Destination IP Address with the address of the node to
which you are connecting in a
back-to-back network or the switch PVC.
- For AIX Version 4.x IP interface configuration (smit
* INTERNET ADDRESS (dotted decimal) (126.96.36.199)
Network MASK (hexadecimal or dotted decimal) (255.255.255.0)
Network Interface (at0)
Connection Type pvc
ATM Server Address ()
Alternate Device (atm0)
Idle Timer ()
Best Effort Bit Rate (UBR) in Kbits/sec ()
* ACTIVATE the Interface after Creating it? yes
After configuring the IP address, the permanent virtual
channel connection is made through SMIT using the SMIT
Or, follow this series of screens:
smit smit devices /user applications / TCP/IP / network
interfaces / network interface selection / pvcs.
- For AIX Version 4.x PVC configuration (smit mkatmpvc):
PVC Description (Optional) ()
* VPI:VCI (0:1000)
Network Interface (at0)
Destination IP Address ()
Automatically Discover Destination IP Address yes
LLC Encapsulation yes
- Verify that you are using the correct VPI:VCI and that the remote
host contains the same VPI:VCI ratio. A ping will hang on
either host if the two ratios are different. As stated
earlier, the VPI value must be set to 0 and the VCI value must be greater than
- If this is a PVC to a switch, check to make sure there
is a proper connection to the ATM switch. This is
usually indicated by a port light on the ATM switch.
Look for wire fault errors in the error log with the
errpt |grep atm command to identify cable problems.
If the SC connectors on your fiber cables are not keyed
or connected with a plastic cover, try reversing the
connectors on one end of the connection.
Many problems occur when the switch is incorrectly
configured. If no one can ping on the switch and you have
double-checked the configuration on AIX, contact the
switch administrator to verify the configuration for a pvc channel.
- Check to see if one adapter has the sonet clock turned on. ping
will hang in back-to-back configuration if no sonet clock is on.
If it is connected to a switch, usually the switch will supply the sonet
clock. Contact the switch administrator to verify that it is sending
- The UNI version is defined at both the switch and the client. The UNI version can be either 3.0 or 3.1. In
addition, the client will set the UNI version to
auto-detect by default. Problems have occurred such that the ATM switch
does not recognize, or is incompatible with, the
auto-detect function. If there is a UNI version mismatch or the
switch is not working with the auto-detect, the ping will hang.
Check the UNI version of the ATM
adapter with lsattr -El atmx or via the SMIT fastpath with
smit chg_atm. Try changing it to the fixed value of
the ATM switch.
- Problems of intermittent communications loss or
of the inability to ping on reboot are often caused by
defects. Please contact your AIX support center to obtain the latest
device driver and common ATM device driver software
[ Doc Ref: 90605195414804 Publish Date: Nov. 14, 2000 4FAX Ref: 7468 ]