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After running a NeXpose scan of one of my servers, I'm getting notice that TCP MD5 signatures may not be enabled. I've looked all over the net and from what I can see this feature should be enabled in the most recent kernels, but I still cannot figure out a way to confirm. Any help would be greatly appreciated.

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Perhaps you are referring to TCP SYN cookies. To enable them:

# echo 1 > /proc/sys/net/ipv4/tcp_syncookies
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