Chapter 4 System Configuration
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Harmonic MediaGrid Release 4.1
Managing Memory Usage by the File System Driver
Verifying ContentServer Disk Space
Follow these steps to verify that each ContentServer has 100% space availability.
To verify space:
1. Using SystemManager, click the
Servers
icon on the
Configuration
tab to access the
Servers
List
page.
2. Locate the
Total Disk Space
and
Free Disk Space
for each ContentServer.
The total Disk Space will vary according to your RAID configuration and drive type. Refer to
a Harmonic MediaGrid Stretch Cluster
for a description of the supported configurations. The Free Disk
Space should be 100%. Refer to the
Harmonic SystemManager User Guide
for more information.
Verifying NFS Share is Exported by ContentBridge
1. Type the following command using the client Linux machine:
showmount –e (
ContentBridge IP address or host name
)
You should see the following output (“cb1.mediagrid.com” is an example host name):
Export list for cb1.mediagrid.com:
/mnt/omfs/mds/csloh/omfs/fs0 0.0.0.0/0.0.0.0
/mnt/omfs/mds/omneon/omfs/fs0 0.0.0.0/0.0.0.0
The output from the command “
showmount -e cb1.mediagrid.com
” lists
/mnt/omfs/mds/
omneon/omfs/fs0
as one of the NFS shares available from the ContentBridge.
To mount the NFS share:
Type the following using the Linux client machine:
mount –t nfs cb1.mediagrid.com:
/mnt/omfs/mds/omneon/omfs/fs0 /mnt
Opening Network Ports to Enable Client Access
Specific network ports must be open to enable client access to Harmonic MediaGrid. This is
particularly important if any security measures, including firewalls, are in place.
Harmonic MediaGrid clients must connect to and communicate on TCP ports 10600-10604;
UDP port 111 must be open as well. Note that these ports must be open for the entire subnet in
which Harmonic MediaGrid is contained.
Contact the customer network administrator for assistance.
Managing Memory Usage by the File System Driver
The amount of memory allocated to memory buffers is controllable. Each client FSD (Linux,
Windows, and Macintosh) allocates memory buffers to optimize performance. This allocation of
memory takes memory away from application use. In general, the memory usage of the FSDs
should be minimized unless an application requires a large number of simultaneous files to be
open.
The following parameters are available to control memory usage by each FSD.
ReadAhead
. This parameter controls the number of slices that are fetched from the server
ahead of where the application is currently reading. The default ReadAhead value is 2 slices
(Mac FSD) or 3 slices (Windows or Linux FSD). Each slice can be 512KB, 1MB, 2MB, 4MB, or
8MB in size. Increasing the ReadAhead value can increase performance for some workflows
