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Getting management data out of WMI from Linux can be challenging but rewarding. This article discusses some of the common techniques that are used to achieve this purpose.
Although Microsoft would prefer you to use Active Directory for implementing domain-wide Group Policy, the legacy NT Domain policy system still works for Windows XP, Server 2003, and all of the older platforms. This means that organizations who login to a Samba or NAS server with Windows networking protocols can still get the benefit of Windows domain policies for certain types of system and user behavior, without running Active Directory.
Few people know it, but Windows has the built-in ability to generate SNMP traps from Eventlog messages, thereby allowing you to monitor for critical events such as login failure, pending drive failures, and other major problems that may otherwise go unnoticed. Here's how it works.
Denial-of-Service attacks are unfortunately somewhat commonplace in this day. Here is a quick guide to understanding how to prepare for these attacks, and how to respond when they inevitably occur.
In order for IP-enabled systems to communicate with each other on the same network, they must first be able to identify the hardware addresses of the other devices. This service is provided by the Address Resolution Protocol. Other ARP services include providing an IP address via Reverse ARP (RARP), advertising a new IP address via Gratuitous ARP (GARP), checking for duplicate addresses via DHCP-style ARP, and more.
IP can be thought of as being like a national delivery service that gets packages from a sender to a recipient, with the sender being oblivious to the routing and delivery mechanisms used by the delivery agent. The sender simply hands the package to the delivery agent, who then moves the package along until it is delivered. That's also how IP works: a system creates an IP datagram, drops it into the network, and leaves it up to the intermediary IP devices to deliver the datagram to the destination system.
IP is an unreliable protocol, and as such, delivery is not guaranteed to occur. However, sometimes a problem crops up that will prevent all datagrams from getting through to their destination. When these kind of non-transient errors occur, IP uses the Internet Control Message Protocol (ICMP) for informing the sending system of the problem, so that it can inform the user or application of the fatal error.