ZyXEL Communications GS2210-24, Руководство пользователя

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GS2210 Series User’s Guide
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H A P T E R
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Error Disable
30.1 Error Disable Overview
This chapt er show s you how t o configur e t he rat e lim it for cont r ol packet s on a por t , and set t he
Swit ch t o t ake an act ion ( such as t o shut dow n a por t or st op sending packet s) on a por t w hen t he
Swit ch det ect s a pr e- configur ed er r or. I t also show s you how t o configur e t he Swit ch t o
aut om at ically undo t he act ion aft er t he er r or is gone.
30.1.1 CPU Protection Overview
Swit ches exchange pr ot ocol cont rol packet s in a net w or k t o get t he lat est net w or king infor m at ion.
I f a sw it ch r eceives lar ge num ber s of cont r ol packet s, such as ARP, BPDU or I GMP packet s, w hich
are t o be processed by t he CPU, t he CPU m ay becom e over loaded and be unable t o handle r egular
t asks pr oper ly.
The CPU prot ect ion feat ur e allow s you t o lim it t he rat e of ARP, BPDU and I GMP packet s t o be
deliver ed t o t he CPU on a por t . This enhances t he CPU efficiency and pr ot ect s against pot ent ial DoS
at t acks or er r or s fr om ot her net w or k( s) . You t hen can choose t o dr op cont r ol packet s t hat exceed
t he specified rat e lim it or disable a port on w hich t he packet s are received.
30.1.2 Error-Disable Recovery Overview
Som e feat ur es, such as loop guar d or CPU pr ot ect ion, allow t he Sw it ch t o shut dow n a por t or
discar d specific packet s on a por t w hen an er r or is det ect ed on t he por t . For exam ple, if t he Swit ch
det ect s t hat packet s sent out t he por t ( s) loop back t o t he Sw it ch, t he Swit ch can shut dow n t he
por t ( s) aut om at ically. Aft er t hat , you need t o enable t he por t ( s) or allow t he packet s on a por t
m anually via t he w eb configurat or or t he com m ands. Wit h er r or- disable r ecover y, you can set t he
disabled por t ( s) t o becom e act ive or st ar t r eceiving t he packet s again aft er t he t im e int er val you
specify.
30.1.3 What You Can Do
• Use t he Er r disa ble St a t u s scr een ( Sect ion 30.3 on page 274 ) t o view w het her t he Sw it ch
det ect ed t hat cont r ol packet s exceeded t he rat e lim it configur ed for a por t or a por t is disabled
accor ding t o t he feat ur e r equir em ent s and w hat act ion you configur e, and r elat ed inform at ion.
• Use t he CPU Pr ot e ct ion scr een ( Sect ion 30.4 on page 276 ) t o lim it t he m axim um num ber of
cont r ol packet s ( ARP, BPDU and/ or I GMP) t hat t he Swit ch can r eceive or t ransm it on a port .
• Use t he Er r disa ble D e t e ct scr een ( Sect ion 30.5 on page 278 ) t o have t he Sw it ch det ect
w het her t he cont r ol packet s exceed t he rat e lim it configur ed for a port and configur e t he act ion
t o t ake once t he lim it is exceeded.
• Use t he Er r disa ble Re cove r y scr een ( Sect ion 30.6 on page 278 ) t o set t he Sw it ch t o
aut om at ically undo an act ion aft er t he er r or is gone.