Installation guide

4-13
SLIP/PPP Problems
• ATCP always executes a PASSIVE open, which in effect forces the attached device to
initiate negotiations.
• If the access server cannot acquire an AppleTalk address from the AppleTalk cache
manager, ATCP cannot reach the OPEN state.
• The peer's MTU may be too low. To determine the size of the MRU, enter the SHOW
PORT LCP STATUS command and check the MRU field.
The peer may negotiate the use of an MRU other than the default of 1500 bytes. If this is
the case, the access server sets the port's MTU to match. AppleTalk does not support
datagram fragmentation. If the peer's MRU is smaller than the size of the AppleTalk
packet, the packet is dropped. AppleTalk packets can be up to 600 bytes in size.
PPP IPXCP (Novell) Connections Fail
Check the following:
• For Novell, IPXCP must be in the OPEN state. To determine the state, enter the SHOW
PORT IPXCP STATUS command and check the State field.
• Novell NetWare must be enabled on the access server or IPXCP does not reach the
OPEN state. Refer to Chapter 14 for more information on troubleshooting IPX
problems.
• The port characteristic IPXCP must be enabled. To determine if IPXCP is enabled,
enter the SHOW PORT IPXCP CHARACTERISTICS command and check the IPXCP
field.
If problems with PPP/IPX negotiations remain after successful dial-in and login, verify the
following:
• Check the PC client status messages.
• Check to see if the port is configured for PPP/IPX.
• Monitor the PPP/IPX negotiations.
• Check to see if PPP/PAP password authentication is enabled.
Checking PC Client Status Messages
Check the remote node access software used on the PC client when connecting. It may
offer status messages giving some indication as to what part of the process is failing.