HP StorageWorks Enterprise File Services WAN Accelerator 3.0.4 deployment guide (AG421-96001, March 2007)

HP STORAGEWORKS ENTERPRISE FILE SERVICES WAN ACCELERATOR DEPLOYMENT GUIDE 121
13 - TROUBLESHOOTING
D
EPLOYMENT PROBLEMS
For more information, see the HP StorageWorks Enterprise File Services WAN
Accelerator Command-Line Interface Reference Manual.
Solution: Use
an Intermediary
Hub or Switch
If you have tried ensuring that speed and duplex settings match as well as manually
setting speed and duplex settings, as described in previous sections, and duplex
mismatch still causes slow performance and lost packets after you deploy in-path HP
EFS WAN Accelerators, introduce an intermediary hub or switch that is more
compatible with both existing network interfaces. HP recommends that you use this
option only as a last resort, if you have not had success with any of the other possible
duplex mismatch solutions.
IMPORTANT: To use an intermediary hub or switch, you must also change your network
cables appropriately.
Problem: Inability to Access Files During
WAN Disruption
If your network requires that clients have continuous access to files, even in the event
of network disruptions that prevent access over the wide-area network (WAN) to the
origin server on which the files are located, consider using Proxy File Service (PFS).
PFS is an optional integrated virtual file server that allows you to store copies of files
on the HP EFS WAN Accelerator with Windows file access, creating several options
for transmitting data between remote offices and centralized locations with improved
performance and functions. Data is configured into file shares by PFS; and the shares
are periodically synchronized (updated) transparently in the background, over the
optimized connection of the HP EFS WAN Accelerator. PFS leverages the integrated
disk capacity of the HP EFS WAN Accelerator to store file-based data in a format that
allows it to be retrieved by Network Attached Storage (NAS) clients.
For more information, see Chapter 9, “Proxy File Service Deployments.”
Solution: Use
Proxy File
Service
If you are using HP EFS WAN Accelerator Models 520, 1010, 1020, 2010, 2020, 3010, or
5010
, you can configure PFS to ensure that remote sites can access files even when a
WAN disruption prevents access to the origin server on which files are located. For
details on configuring PFS, see Chapter 9, “Proxy File Service Deployments.”
Problem: Network Asymmetry
If some of the connections in a network are optimized and some are passed-through
unoptimized, it could be due to network asymmetry. Network asymmetry causes a
client request to traverse a different network path than the server response. Network
asymmetry can also break connections.