The Linux Networking Overview HOWTO: Enterprise Linux Networking
10. Enterprise Linux NetworkingIn certain situations it is necessary for the networking infrastructure to have proper mechanisms to guarantee network availability near 100% of the time. Some related techniques are described in the following sections. Most of the following material can be found at Linas excellent website: http://linas.org/linux/index.html and in the Linux High-Availability how-to10.1 High AvailabilityRedundancy is used to prevent the overall IT system from having single points of failure. A server with only one network card or a single SCSI disk has two single points of failure. The objective is to mask unplanned outages from users in a manner to let users continue to work quickly. High availability software are a set of scripts and tools that automatically monitor and detect failures, taking the appropriate steps to restore normal operation and to notifying system administrators.10.2 RAIDRAID, short for Redundant Array of Inexpensive Disks, is a method whereby information is spread across several disks, using techniques such as disk striping (RAID Level 0) and disk mirroring (RAID level 1) to achieve redundancy, lower latency and/or higher bandwidth for reading and/or writing, and recoverability from hard-disk crashes. Over six different types of RAID configurations have been defined.There are three types of RAID solution options available to Linux users: software RAID, outboard DASD boxes, and RAID disk controllers.Software RAID : Pure software RAID implements the various RAID levels in the kernel disk (block device) code.Outboard DASD Solutions : DASD (Direct Access Storage Device) are separate boxes that come with their own power supply, provide a cabinet/chassis for holding the hard drives, and appear to Linux as just another SCSI device. In many ways, these offer the most robust RAID solution.RAID Disk Controllers: Disk Controllers are adapter cards that plug into the ISA/EISA/PCI bus. Just like regular disk controller cards, a cable attaches them to the disk drives. Unlike regular disk controllers, the RAID controllers will implement RAID on the card itself, performing all necessary operations to provide various RAID levels.Related How-tos:http://sunsite.unc.edu/mdw/HOWTO/mini/DPT-Hardware-RAID.htmlhttp://sunsite.unc.edu/mdw/HOWTO/Root-RAID-HOWTO.htmlhttp://sunsite.unc.edu/mdw/HOWTO/mini/Software-RAID.htmlRAID at linas.org:http://linas.org/linux/raid.html10.3 Redundant networkingIP Address Takeover (IPAT). When a network adapter card fails, its IP address should be taken by a working network card in the same node or in another node. MAC Address Takeover: when an IP takeover occurs, it should be made sure that all the nodes in the network update their ARP caches (the mapping between IP and MAC addresses).See the High-Availability How-To for more details: http://sunsite.unc.edu/pub/Linux/ALPHA/linux-ha/High-Availability-HOWTO.html
>
Wyszukiwarka
Podobne podstrony:
networking overview howto 9 ogqpxq72nbf7kqln4xdtyu3p2okvo6aql34xpfanetworking overview howto 11 birdddbhhxei3y75xn3dyxnxyf55mkjjwnxktuqnetworking overview howto bnx26jhbkwwpw6yzws4tkldczwdoxxugviqrtpynetworking overview howto 12 yhtznaj2byamnufwibq2dq3qmq7lar23akyornanetworking overview howto 8 ro46eiel3q5crthpoeucm2aoc3ryi6t7frzn2yy ro46eiel3q5crthpoeucm2aoc3ryi6t7networking overview howto 1 mim6i7dsp32byq2fro3le5haz7d3zbl7le3imhqnetworking overview howto 2 caiprehshglxfui7peanqd752dkbefhdgn5zxjqnetworking overview howto 6 xnvzjf5vxjrzc7y54xczl5bdzeeaqvleonka6lq xnvzjf5vxjrzc7y54xczl5bdzeeaqvlenetworking overview howto 7 4jcki7zegaz5gvckfp3gprrctzflbm4xnoe4dtynetworking overview howto 5 mt4owegnyy2cmmmhnubg5zzp56a7dogr7ckvweqpostgresql howto 10 4yctbmdygvosxskplagrc3lw4rwfp7x2owdlrhqethernet howto 10ftape howto 10access howto 10esperanto howto 10więcej podobnych podstron