Ping to Windows Server 2012 with Direct Access fails

Problem:┬áPing from Linux computers to Windows Server 2012 with Direct Access fails for hours (no response) although connectivity is working (eg. HTTPS) Discussion:┬áPing from other windows machines and Cisco machines worked, but from Linux machines ping was not answered. I tried to find the difference between those ICMP Echo Request Packets, and reduced it to …

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WScale and Cisco Content Switch CSS.

Problem: Windows 7 clients wait 5 seconds to send simple HTTP requests to a web server behind a cisco CSS content switch. But there is no delay when the client connects directly to a web server behind the CSS. Description: I found one difference between CSS and non-CSS connects: the TCP WSCALE option. When the …

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Windows Network Load Balancing NLB and Cisco Routers/Switches

Problem: Windows NLB IPs are are not reachable through and from Cisco routers and switches. NLB services could be IIS arrays, Exchange CAS arrays, etc. Solution: NLB mode was set to Multicast. In this mode Windows incorrectly uses multicast mac addresses. Set the NLB mode to Unicast and configure static mac address table entries on …

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