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tcpdump command

Ubuntu / Debian Linux: Setup An ISC DHCP Server For Your Network

How do I setup a DHCP server for my local area network (LAN) using Debian Linux 6 or Ubuntu Linux server running on my IBM hardware?
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Verify: Keepalived IP Failover Working Or Not With tcpdump Command

I've installed keepalived IP failover software as described here. But how do I verify it is working or not?
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tcpdump: Monitor ALL eth1 Traffic Except My Own SSH Session

I'm using tcpdump to dump, debug and monitor traffic on a network. However, there is lots of noise and I would like to exclude ssh from my dumps. How do I monitor all traffic except my ssh session?
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Linux Tune Network Stack (Buffers Size) To Increase Networking Performance

I've two servers located in two different data center. Both server deals with a lot of concurrent large file transfers. But network performance is very poor for large files and performance degradation take place with a large files. How do I tune TCP under Linux to solve this problem?
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TCPDump: Capture and Record Specific Protocols / Port

Q. How do I capture specific protocol or port such as 80 ( http ) using TCPDump tool under Linux / UNIX? How do I recording Traffic with TCPDump and find problems later on?
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FreeBSD / OpenBSD: PF Firewall Filter Large Number Of Subnets and IP Address

Q. How do I filter larger number of subnets and IPs using OpenBSD's pf firewall under FreeBSD 7.x server? How do I log all dropped packets from such ips? How do I block upto 10000 IPs or subnet without any performance penalty?
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Monitor HTTP Packets ( packet sniffing )

How do I monitor and analyze data transferred via HTTP (apache or lighttpd or nginx webserver) for debugging and security purposes?
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