iTP Secure WebServer System Administrator's Guide (iTPWebSvr 6.0+)

Installing the iTP Secure WebServer
iTP Secure WebServer System Administrator’s Guide—523346-002
2-4
Preparing Your System for the iTP Secure
WebServer
one TCPSAM (TCP socket access point) process must be running. If not all of
these processes are running, the Auto-Accept feature will not be used. The iTP
Secure WebServer will fall back to using the conventional support for TCP/IP.
For information about configuring for Parallel Library TCP/IP, refer to the TCP/IP
(Parallel Library) Configuration and Management Manual.
This manual is especially important for the configuration of the LAN adapter(s).
The access list of the SAC needs to include all CPUs designed to run httpd
servers. This is not new information, but just a reminder to double-check the
configurations because the list now should contain more CPUs than previously. In
conventional TCP/IP, a TCP/IP process is usually running on 2 CPUs - a primary
and a backup.
For Parallel Library TCP/IP, if the application is running on all the other 14 CPUs,
then all of those need to be Parallel Library TCP/IP-enabled and must be in the
access list.
Parallel Library TCP/IP-enabled means that there should be a TCPMON process
running on that CPU. In order for the httpd servers to function properly, all these
processes must be in place. Socket errors will be reported if a TCPMON is not
running on a CPU that attempts to run a httpd process. The httpd server is
designed to retry the bind request if it fails. Repeated bind failures may indicate
that a CPU is not Parallel Library TCP/IP-enabled.
°
Use One TCPSAM Process
Ensure that there is one TCPSAM process pair running on any two CPUs in the
system. It is recommended that you use only one TCPSAM process pair - even
where you are using more than one IP address. Unlike the conventional TCP/IP
processes, one TCPSAM process can provide socket interfaces for all IP
addresses configured in the Parallel Library TCP/IP environment. If you use more
than one, two httpd servers may attempt access to the same port and therefore
generate EADDRINUSE socket errors.
°
Use Static Servers
It is strongly recommended that you run as many static servers as you may need.
Again, this is not new information. Creating dynamic servers is known to be
expensive and will severely affect response time - especially for the request
waiting for the dynamic server to be created. In addition, dynamic servers may
drop one or two connections when the Deletedelay effect occurs. Because all of
the httpd servers are designed to run on high pin, creating more servers at the
startup should not create a resource problem.
°
Specify a Larger Tandem_Receive_Depth
The range is 1 to 255. The default is 50. Selecting a larger number prevents extra
pathsends and possible socket migration. When the connection request is sent to a
server that is not running on the same CPU as the original listening agent, a socket
migration occurs and a performance penalty is incurred. A larger number also
prevents the creation of dynamic servers. Creating an additional httpd server on a