Posts Tagged ‘ISCSI’

In Windows Server 2008 or Windows Server 2008 R2 environment, if the network environment is set to enable Delay ACK and storage is connected with iSCSI, an iScsiPrt error is output to the System Event Log when a general operation is executed

Monday, August 22nd, 2011

Disable Delay ACK

Setting the Registry value TcpAckFrequency to 1
according to the technical information below will disable Delay ACK. This will
prevent the resend processing time from going to 5 frame/sec when a packet is
dropped. Using this method will not prevent packets from being dropped, but
even if they are dropped the resend processing delay will be improved, so that
time outs will not occur.


Entry: TcpAckFrequency
Value Type: REG_DWORD, number
Range: 0-255
Default: 2

Q: Why do I see DNS Failure on the iSCSI network name cluster resource?

Sunday, June 13th, 2010

A: The default network properties will force the Network Name resource to attempt to register itself with a DNS Server. This may result in slower than expected iSCSI resource group movement between Windows Storage Server 2008 cluster nodes. The recommendation is to remove the DNS registration requirements by adjusting the appropriate network properties.

1. Open the Network Sharing Center on one of the Windows Storage Server 2008 systems.

2. Select Manage network connections.

3. Select Properties for the iSCSI Network.

4. Select Properties for Internet Protocol Version 4 (TCP/IPv4).

5. Select the Advanced tab.

6. Select the DNS tab.

7. Deselect the Register this connection’s addresses in DNS.

8. Close the Properties for the iSCSI Network.

9. If there are any additional iSCSI networks, repeat Step 3 to 8 for each one.