12

Troubleshooting

This chapter contains information to help solve problems when booting and using your network computer. Table 12-1 lists identified problems and the page numbers to locate possible solutions.

Table 12-1   Possible Problems

Problem	Page
Boot host does not respond	12-2
Network computer does not respond to a ping	12-3
Duplicate IP address message	12-3
Network computer cannot locate os file	12-4
Network computer cannot locate .tbl files	12-4
Network computer cannot locate font files	12-5
HostMenu does not display any xdm hosts	12-5
xdm login window does not appear	12-5
xdm login window reappears instead of starting session	12-6
Control-C does not cause an interrupt	12-6

Boot host does not respond

• Verify that the boot host is configured to support the boot method you selected. Supporting host files may include inetd.conf, bootptab, exports, hosts, and ethers.
• Use the ps command on the boot host to verify the supporting daemon(s) are running. The daemons may include: inetd, nfsd, tftpd, bootpd, and rarpd.
• If you are booting from NVRAM, use the network computer Boot Monitor to verify the correct values are assigned for the following commands:
  • Network computer IP address (iaddr) or node number (dnode)
  • Boot host IP address (ihost)
  • Subnet mask (imask)
  • Gateway address (igate)
  • Boot method (bmethod)
  • Boot path (bpath)
  • Boot from (bafrom set to NVRAM)
• If you are booting from NETWORK, use the network computer Boot Monitor to verify the correct values are assigned for the following commands:
  • Boot method (bmethod)
  • Boot from (bafrom set to NETWORK)
• Use the network computer Boot Monitor to ping the boot host, for example:

  BOOT > ping <host_ipaddr>

  If the host does not respond, use the ifconfig command on the host to verify the host's subnet mask and gateway address. The ifconfig command is also used to change the subnet mask and gateway address if necessary.

• If the host has an ethernet switch, make sure it is set to the proper position for thicknet or thinnet.

Network computer does not respond to a ping

• Verify that the network computer is booted.
• Use the network computer Boot Monitor report command to check the network computer's ethernet setting. If incorrect, set it to match your Ethernet specification using the lan command. See the NCBridge Reference Manual for directions on using this command. This is the lan output from the report command:

lan: Am79C937 Ethernet -Chip ID 2625 autonegotiated half-duplex, 100 Mbps

Duplicate IP address message

This can indicate two different problems: either there are two devices using the same IP address, or there is a mismatch between the ethernet and IP addresses in the host files or in the router ARP tables.

• To determine if there are two devices using the same IP address, go to a different device and ping the duplicate IP address. If two responses come back, change the IP address on one of the devices. Be sure to save the new address. You may also have to change supporting files on the host, such as /etc/hosts, /etc/ethers, bootptab, and change entries in the ARP table (arp command) to ensure the correct ethernet and IP addresses are used.
• If the network computer is using the same IP address as a previous device (that has been removed from the network), then the problem is a mismatch between the ethernet and IP addresses. To correct this situation, change the files where the ethernet and IP addresses are used, such as /etc/ethers, bootptab, and change entries in the ARP table (arp command). The network administrator should flush the ARP table in the router.

Network computer cannot locate os file

• Verify that the boot path is specified correctly and matches the actual file location on boot host. If using secure tftp, the secure directory should not be specified as part of the boot path. For Silicon Graphics hosts, the secured boot path should not have a leading slash. For other UNIX hosts, the secured boot path should have a leading slash.
• Verify that you are using the correct os file (os.330, os.500, or os.900), and that it has world read permission. Use chmod command to change permission.
• On Hewlett-Packard hosts, verify that tftp is set up properly. On some Hewlett-Packard hosts, there must be a tftp entry in the password file. The secure directory is specified in the password file as if it were a home directory. Also, if tftp is in the inetd.sec file, make sure the network computer is listed as an authorized device.

Network computer cannot locate .tbl files

Verify the primary and secondary file hosts, access methods, and paths:

• If you are debugging a centralized system, or if the network computer is not booted, check the primary and secondary file_access, file_host_name, and file_path entries in the xp.cnf file. See How the X Server Builds the Font Database.
• If the network computer is booted, use the Console window to see the host, method, and path the network computer tried. Use the Left and Right mouse buttons to scroll through the window. You can also use Setup to view the host file access information.
• Verify that the appropriate daemon is running on the host for the specified access method.
• Verify that the .tbl files are in the proper location and have world read permission. If you are using secure tftp, ensure that the .tbl files are in the secure directory. If the .tbl files are not in the secure directory, either move them to the secure directory or use NFS to download them.

Network computer cannot locate font files

• Follow the previous procedures for Network computer cannot locate .tbl files to verify that the network computer is locating the fonts.tbl file.
• Verify that the fonts.tbl file specifies the correct paths to the font directories. If NFS is used, the full pathname to the NFS mount point must be specified if NFS is used.
• Verify that the fonts.dir and fonts.alias files exist and are readable.
• Verify that the fonts.dir and fonts.alias files contain the correct paths to the actual font files.

HostMenu does not display any xdm hosts

• Use the ps command to verify that the xdm daemon is running on the host.
• Check the Host Connect Method with Setup. Drag on Configuration Summaries and release on X Environment. Verify that the Host Connect Method is set to HostMenu.
• Verify that the xdm-error and xdm-pid files have world write permission in the xdm-config file.

xdm login window does not appear

• Use the ps command to verify that the xdm daemon is running on the host.
• Check the Host Connect Method with Setup. Drag on Configuration Summaries and release on X Environment. Verify that the Host Connect Method is set to XDMCP Direct, and that the log in host is specified.
• Verify that the xdm-error and xdm-pid files have world write permission in the xdm-config file.

xdm login window reappears instead of starting session

• Verify that the X startup file contains a valid session control client. Ensure that either the system-wide Xsession (or Xinitrc on Sun hosts) or users .xsession (or .xinitrc on Sun hosts) file ends with a client that is not running in the background. Verify the path to the session control client.
  To correct the problem, try using failsafe mode: When the xdm login window appears, type in user name and password and press the F1 key (instead of Enter). If nothing happens, then the failsafe feature is not enabled on that host, and you must log in by another method.
• Verify that the session control client is executable. Use the chmod command, if necessary, to make the session control client executable. Try using failsafe mode to correct the problem.
• The X startup file may not be executable. Use the chmod command, if necessary, to make the X startup file executable. Try using failsafe mode to correct the problem.
• Environmental variables may not be set. Verify that the X startup file sets any environmental variables that are required by the session control client. Try using failsafe mode to correct the problem.

Control-C does not cause an interrupt

• Set the interrupt variable in each user's .cshrc (c shell) or .profile (Bourne shell) file. Use the format:

  stty intr '^C'