User manual

The WebMux Pro and Model WM108E User Guide – Version 5. 8 Rev15

from outside through server farms to the servers. After the connection closed

from the servers to the outside computer, it will wait this timeout minutes before it

removes that from the tracking table. Setting this too long will cause WebMux

allocating too much memory, thus reduce the memory for other functions. The

default value is 15 minutes. This function has no effect in Out-of-Path mode.

Server Scan Mode:

WebMux talks to the real servers in the farm through the layer 4-7 protocols

every few seconds. This is important process for monitoring servers’ health

situation. If there are a lot of farms and a lot of servers, WebMux may not be able

to get around checking all the servers in few seconds. In concurrent mode,

WebMux will start multiple protocol scanners to chat with servers concurrently.

Concurrent mode uses more memory, may have other side effect. For most

setups, sequential scan is recommended.

URL for Custom Service Check:

Sometimes WebMux built-in server health check is not enough for the special

needs. When one ASP/JSP server’s output is depends on the database server

and database server connection is down, one might want to redirect the traffic to

a different server, or make the ASP server out of services. To accomplish that,

WebMux allows a farm being set using a “service” called “custom defined TCP

service”. It will then call the CGI’s URL on the server defined in this field. This will

involve a custom developed CGI code by your software developer on your server

and place it on the path. Upon success the page should return HTTP response

code 200 and a plain text page beginning "OK". The URL is truncated to 255

bytes (to be a string of at most 256 bytes with a terminating null). The response

from the server must fit in 4k, including all non-display tag and headers etc. This

custom CGI code must complete within 15 seconds or the server considered

dead. Please see appendix 5 for sample code.

UDP NTP Time Server IP Address:

From version 5.4, WebMux can sync its internal clock with any UDP NTP server.

By default it points to a tier 2 NTP server. You can also set it to your Internet NTP

server, or wipe out the entry to not sync to any NTP server.

Reset Stranded TCP Connections:

When a server failed to function, there could be many TCP connections still in

TCP_WAIT state. If this set to “Yes”, when client tries to access the failed server,

WebMux will pretend the server sending TCP Reset to the client, thus free all the

TCP_WAIT state connections. By default this setting is “No” to be consistent

with prior versions.

Reboot:

Changes to "server gateway address", "server farm network mask", "WebMux

http control port", and “WebMux https control port” requiring a reboot for the new