RHEL 6.6/CentOS 6.6 vs Hyper-V 2012R2 | ||||||
| posted by Jean-Francois Panisset on Nov. 3, 2014, 11:25 a.m. (1 day ago) | ||||||
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| Thread Tags: discuss-at-studiosysadmins | ||||||
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An upgrade from CentOS 6.5 to 6.6 killed DNS for a guest VM on top of Hyper-V 2012R2. A bit of digging turned up that the kernel in 6.6 supports TCP Offload on Hyper-V: and that seemed to be messing with DNS UDP packets. Turning off TCP offloading makes things work again. The underlying physical NIC is a Myricom 10GbE. Still trying to figure out the "best" way to disable TCP Offload for CentOS 6.6 guests... JF |