tcptrack is a sniffer which displays information about TCP connections it sees on a network interface. It passively watches for connections on the network interface, keeps track of their state and displays a list of connections in a manner similar to the unix ‘top’ command. It displays source and destination addresses and ports, connection state, idle time and superbly impressive – bandwidth usage.

A server admin must have.

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Advanced Policy Firewall (for cPanel)

More retro software that has been with us for years – APF – Advanced Policy Firewall. A brilliantly robust and fool proof Linux script that acts as a wrapper for iptables.

Here’s how I configure it for all the WHM/cPanel boxes I commission, although you can configure it for non-cPanel servers, just adjust your ports accordingly. Continue reading “Advanced Policy Firewall (for cPanel)”

[Snippet] Checking a Global Catalog is really a Global Catalog

Use an LDAP browser or ADSI Editor to connect to the port 3268 Global Catalog communication is performed over TCP port 3268, regular LDAP lookups are sent to TCP port 389.

After assigning a GC role to a server, check its Directory Services event log for event number 1119, which indicates successful obtaining a role of a Global Catalog server