Error: "420 TCP Read Error"
(Last modified: 02Dec2005)
This document (10008678) is provided subject to the disclaimer at the end of this document.
fact
Novell GroupWise 5.0
Novell GroupWise 5.1
Novell GroupWise 5.2
Novell GroupWise 5.5
Novell GroupWise 6.0
Novell GroupWise 6.5
Novell GroupWise Internet Agent
symptom
Error: "420 TCP Read Error"
Large number of TCP Read errors on GWIA or SMTP Gateway
fix
Apply the latest Support Pack for NetWare. This update contains the latest version of the TCPIP stack. Once the support pack has been applied, set the following parameters at the server console prompt:
SET USE SPECIFIED MTU = ON
SET MAXIMUM INTERFACE MTU = 1500
These parameters can be added to the AUTOEXEC.NCF. To view the current setting or to see a description and parameter range limits, enter either "SET USE SPECIFIED MTU" or "SET MAXIMUM INTERFACE MTU" at the console prompt. These set parameters are not supported with versions earlier than IWSP5B of the NetWare TCP/IP stack.
NOTE: If the "No ECB available count" is high, increase the Maximum Packet Receive Buffers. The server must be rebooted for the change to take effect. The No ECB available count is found in MONITOR-LAN/WAN DRIVERS-select an interface and press <TAB>. Look at Receive discarded, no available buffers:.
-If the above steps did not work you can look into the following areas:
Make sure the Static Default route is pointing to the most direct route to the router connecting the server to the Internet.
Contact ISP to test the hardware
SET ALWAYS ALLOW IP FRAGMENTATION = ON
SET MINIMUM PACKET RECEIVE BUFFERS = 500 or greater
SET MAXIMUM PACKET RECEIVE BUFFERS = 2000 or greater
SET MAXIMUM PHYSICAL RECEIVE PACKET SIZE = 4212
If these do not resolve the problem, then try this:
SET USE SPECIFIED MTU = ON
SET MAXIMUM INTERFACE MTU = 576
document
| Document Title: | Error: "420 TCP Read Error" |
| Document ID: | 10008678 |
| Solution ID: | 1.0.628794.2048517 |
| Creation Date: | 09Mar1999 |
| Modified Date: | 02Dec2005 |
| Novell Product Class: | Connectivity Products Groupware NetWare Novell BorderManager Services |
disclaimer
The Origin of this information may be internal or external to Novell. Novell makes all reasonable efforts to verify this information. However, the information provided in this document is for your information only. Novell makes no explicit or implied claims to the validity of this information.
Any trademarks referenced in this document are the property of their respective owners. Consult your product manuals for complete trademark information.