Troubleshooting guide

6
Special Considerations
• If you do not have access to the local console, then use the modem port on the redundant switch.
This method requires redundant Release 2 switch cards and redundant modems and the ability to
dial in to the LightStream 2020 chassis, using the other Release 2 switch card and modem.
Dial in to the LightStream 2020 chassis and determine the address of this switch card (the one to
which the modem is attached).
Type the following commands at the TCS HUB prompt:
set {sa | sb} modem baudrate {2400|9600}
init {sa | sb} modem
Use the address of the other switch. That is, if you are connected to Switch Card A, specify sb in
these commands, and if you are connected to Switch Card B, specify sa in these commands.
Specify the baud rate to which the modem is set.
Loss of Carriage Return or Echo Functionality
A terminal may lose carriage return or echo functionality.
Workaround: Execute the bash tset command to restore the lost property.
LIGle00221 CLI and TCS Can Show Different Primary Switches
The primary TCS hub and the primary (active) switch fabric may be on different switch cards in a
redundant system.
The CLI show chassis primaryswitch command indicates which switch fabric is active. The
primary TCS hub is indicated in any of the following three ways:
1 The following TCS command:
status { sa | sb }
2 The use of uppercase letters in the TCS HUB prompt. That is, the prompt TCS HUB <<B>>
indicates that the TCS hub on the card in Slot B is active, and the prompt tcs hub <<b>>
indicates that it is secondary. (In both cases, the name of the hub card to which you are connected
is indicated by the letter in brackets.)
3 The LED labelled TCS SEL on the switch card is lit.
Changing Primary Switch Causes Chassis to Reboot
On systems with at least one Release 1 switch card, using a CLI command to change which switch
is primary causes the chassis to reboot. The CLI command is set chassis primaryswitch.
LIGle00225 Rates Can Be Set to Unsupported Values on Low-Speed Card
The configuration tool and CLI allow rates to be set to 6 Mbps aggregate for low-speed cards. The
maximum throughput per port for the low-speed card is about 4.1 Mbps and 4600 frames/sec, when
you are using committed traffic and an 88-byte frame. If the rate is set above this limit, the excess
may be dropped.
Workaround: Do not set rates higher than 3.84 Mbps per port on low-speed cards.