Environment
Novell ZENworks 10 Configuration Management with Support Pack 3 - 10.3 Patch Management
Situation
Patch download process appears to stall out and hang. No patches download.
Downloading patches or any other content from the Internet will stall out. The download starts but randomly will stop downloading data and leave the download process running, even though there is no more data being received.
This was verified using wget to try and download files from Internet sources. When running the wget command the files would start to download at a very slow rate of about 7-18kbs. The file would stop downloading somewhere between 200KB and 2.1MB, leaving the wget process running until manually terminated.
Downloading patches or any other content from the Internet will stall out. The download starts but randomly will stop downloading data and leave the download process running, even though there is no more data being received.
This was verified using wget to try and download files from Internet sources. When running the wget command the files would start to download at a very slow rate of about 7-18kbs. The file would stop downloading somewhere between 200KB and 2.1MB, leaving the wget process running until manually terminated.
Resolution
Turn off TCP window scaling:
On Windows run the following command:
netsh interface tcp set global autotuninglevel=disabled
On Linux run the following command:
sysctl -w "net.ipv4.tcp_window_scaling=0"
This will change the settings so that downloads will start working.
To make this change permanent on SLES edit /etc/sysctl.conf and add the following line:
net.ipv4.tcp_window_scaling = 0
Reboot the server and verify that patch downloads are working.
On Windows run the following command:
netsh interface tcp set global autotuninglevel=disabled
On Linux run the following command:
sysctl -w "net.ipv4.tcp_window_scaling=0"
This will change the settings so that downloads will start working.
To make this change permanent on SLES edit /etc/sysctl.conf and add the following line:
net.ipv4.tcp_window_scaling = 0
Reboot the server and verify that patch downloads are working.