Excessive Retries Occur when a Provisioning Server Target Device is Deployed on a XenServer Platform

Excessive Retries Occur when a Provisioning Server Target Device is Deployed on a XenServer Platform

book

Article ID: CTX117491

calendar_today

Updated On:

Description

When the Citrix Provisioning Server target device is deployed on a XenServer platform, the device may experience some of the following symptoms:

  • Excessive retries while performing a physical to virtual target build

  • Slow ICA performance when using XenDesktop

  • Freezing or locking with XenDesktop while using Windows XP Service Pack 2

  • vDisk retries during normal operation when a Windows XP Service Pack 2 virtual machine is already online and in waiting mode

  • Slow hosted application launch when using Presentation Server 4.5 and publishing applications in XenDesktop

"Retry" definition: The client’s driver performs a vDisk I/O by sending a request to the Provisioning Server. If a transaction fails because of a timeout (which is a no-reply timeout), the driver tries to receive the packet again. The retry number is accumulated by the client and reported to the client’s statistics tray.

Environment

Caution! Using Registry Editor incorrectly can cause serious problems that might require you to reinstall your operating system. Citrix cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Be sure to back up the registry before you edit it.

Resolution

As a workaround, disable checksum offloading on target device's network adapter.

Caution! Refer to the Disclaimer at the end of this article before using Registry Editor.

Complete the following procedure after starting the master target device in Private Image mode:

  1. Open Start > Run, type regedit, and then click OK.

  2. Locate the following registry subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

  3. In the right pane, ensure that the DisableTaskOffload registry entry exists. If this entry does not exist, use the following steps to add the entry:

    1. On the Edit menu, go to New and then click DWORD Value.

    2. Type DisableTaskOffload and then press Enter.

  4. Click DisableTaskOffload.

  5. On the Edit menu, click Modify.

  6. Type 1 in the Value field and then press Enter.

  7. Close Registry Editor.

    Additionally Check for the following :
    1. All the PVS server are on the same version 
    2. All the PVS server are on network hosts which are accessible to one another
    3. The storage used on each is local (preferred) , if using a shared network storage or an external storage , no latency in accessing each
    4. Re run configuration wizard on each to verify that no mismatch is observed 

Problem Cause

Offload parameters are not compatible with the Provisioning Server network stack. Citrix recommends disabling features such as TCP Offload on the network adapter for the target device.
Configuration differences between PVS servers of the same farm 

Issue/Introduction

This article provides a workaround when excessive retries occur after a Provisioning Server Target Device is deployed on a XenServer Platform.
Powered by Wolken Software