Month: June 2014

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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“dd” shows its progress

Problem: “dd” is a useful tool on linux. E.g. you can copy a disk image or wipe a disk, etc. But dd doesn’t show you any progress indicator, and you don’t know how long you have to wait until it has finished. Solution:   send signal USR1 to the dd process and it will show you how much data …

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