McDATA Eclipse 2640 SAN, Administration And Configuration Manual

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4
Configuring iSAN Connections
4-13
Configuring TCP Ports for iFCP
Router without a XFER_RDY from the target device.
Specify the maximum amount of buffered data, in
kilobytes, in the text field. The memory limit is a single
pool for all Fabric Channel login sessions.
• Selecting the
Transmit Buffer Management option
allows the user
to manage the amount of Fabric Channel receive buffers that
an iFCP port has for receiving the Fabric Channel frames
forwarding from Fabric.
In cases where ELSs are issued in the middle of large amount
of data packets and the iFCP/TCP side is connected to a slow
link (e.g. OC3 link), user may experience ELS timeout. ELS
timeout occurs when ELSs have command timeout values
shorter than normal Read / Write commands and when ELSs
are queued behind the large amount of Read/Write data.
Reducing the number of Fabric Channel receive buffers will
cause congestion back into any attached device or fabric to
occur sooner or for lower amounts of outstanding data, which
then minimizes the ELSs timeout condition.
NOTE:
Transmit buffer option may cause head of line blocking and
congestion which might lower the performance of the system instead of
helping it.
• Select the
Defaults
button to reset all options in the iFCP area
to the following:
• Compression Level - Off
• Compression Method - LZO
• Selective ACKnowledgement - enabled
• FastWrite - disabled
• Transmit Buffer Management - disabled