F5 data flood

Problem: A F5 load balancer LTM sends lots of data to some clients. Sometimes this fills up all the available bandwidth with 1 Gbit or more. At the same time the input traffic does not raise. The traffic charts look like if F5 is attacking some clients (reversed DDoS :-) ) Discussion: After some time of staring …

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Ping to Windows Server 2012 with Direct Access fails

Problem: Ping from Linux computers to Windows Server 2012 with Direct Access fails for hours (no response) although connectivity is working (eg. HTTPS) Discussion: Ping 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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