Manuale d’uso / di manutenzione del prodotto X908 del fabbricante Allied Telesis
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Te c h n i c a l G u i d e alliedtelesis .com x How T o | C613-16128-00 REV E Introduction ISPs tr anspor t lar ge volumes of data. They often ha ve to pa y lar ge amounts of money to tr anspor t their data through hired links, or thro ugh other pro vider s' networ ks.
I n tr od u ctio n Page 2 | Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Co n te n ts Introduction . ............ ............... ............ ............ ............ ............ ............... ............ ..
Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 3 I n trod u ctio n BGP: Route Map Fil teri ng Example ... ............ ............ ............... ............ ............ ............... ............ .. .
BGP: Co n cepts a n d T ermi n olog y Page 4 | Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes BGP: Concepts and T er minology Before mo vi ng on to look at the filtering proc esses, it is impor tant to fir st hav e some under st anding of cer tain aspects of how BG P w or ks.
Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OS PF Ro u tes | Page 5 BGP: Co n cepts a n d T ermi n olog y Update attr ib u tes As mentioned abo ve , each BGP up date message contains a set of attr ibut es.
BGP: Overview of t he Available Filter T ypes Page 6 | Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes BGP: Ov er view of the A vailab le Filter T ypes The following sections describe the var ious types of filter s that can be applied to BGP updates and the hierarchy of the filters.
K EY W ORD IN COMMAND DEFINABLE FILTER WA Y TO APPLY FIL TERING AC L access-list Ye s Distribute list distr ibute-list Ye s Prefix list prefix-list Ye s Ye s AS path list as-pat h Ye s Filter list fil.
Hierarch y of the Di ffere n t Filters Page 8 | Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Hier archy of the Diff erent Filter s For distr ibute filter s (A CLs), path filter s, and prefix filter s, the order of application is not impor tant.
Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OS PF Ro u tes | Page 9 Hierar ch y of the Differ e n t Filters Basic co n fig u ratio n This configuration gets the neighbor relationship establis hed and some routes exchanged. AlliedW are Plus switch Create the second VLAN an d associate por t 1 .
Hierarch y of the Di ffere n t Filters Page 10 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Co n firmi n g the n eighbor r elatio n ship Check that each switch sees the interface rout e adver tised from the other switch.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 11 BGP: Co n fig u ri n g Distrib u te Filters BGP: Configur ing Distr ibute Filter s Distr ibute f ilter s use A CLs (Access Control Lists) to filter par ticular routes on the ba sis of their prefix es.
BGP: Co n fig u ri n g Dis trib u te Filters Page 12 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Usi n g A CLs as filters When y ou ha ve created an A CL, y o.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 13 BGP: Co n fig u ri n g Distrib u te Filters Filter o u t a ra n ge of pref ix le n gths This example demonstrates the effect of the exact par ameter in the A CL by discarding all routes to 52.
BGP: Co n fig u ri n g Dis trib u te Filters Page 14 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Set that ACL as the filter for the BGP neighbor 45.45.45.46: 3. Check that the IP r oute table now includes all the r outes.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 15 BGP: Co n fig u ri n g Distrib u te Filters Use a nu mbered A CL i n stead of a n amed A CL This example demonstrates a numbered A CL by discarding all routes to 52.
BGP: Co n fig u ri n g Dis trib u te Filters Page 16 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes 4. Check that the IP r oute table no longer includes 52.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 17 BGP: Co n fig u ri n g AS Path Filters BGP: Configur ing AS P ath Filter s T o configure path filters we need to fir st under stand something about AS path lists and how to use them.
BGP: Co n fig u ri n g AS Path Filters Page 18 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Usi n g AS path lists as path filters When an AS path list has been.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 19 BGP: Co n fig u ri n g AS Path Filters Explicitly include a neighbor 4. Shut down the neighbor , and then bring it up again. awplus(config-router)# neighbor 45.
AS path access list list1 deny 23456 permit 34568 BGP: Co n fi g u ri n g AS Path Filters Page 20 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes A n other example An outgoing filt er tha t u ses an AS-path list ip as-path access-list example deny ^$ ip as-path access-list example permit 34567 neighbor 45.
BGP route table Flags: >=Best route for the gi ven prefix, *=Unreachable next hop, W=Withdrawn m=Community, a=Aggregate route, s=Aggregate Suppresse d, D=Damped Learned from: L=Local, e=eBGP Peer, .
BGP: Co n fig u ri n g Pref ix Filters Page 22 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes BGP: Configur ing Prefix Filter s Prefix filters use prefix lists to filter par t icular routes on the basis of the ir prefix es.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 23 BGP: Co n fig u ri n g Pref ix Filters Usi n g pr efix lists as pr efix filters When y ou ha ve created a p.
BGP: Co n fig u ri n g Pref ix Filters Page 24 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Filter o u t a ra n ge of differ e n t prefix le n gths This example f ilter s out routes to 45.0.0.0 w ith prefix le ngths in the range 5-8, accepts routes to 52.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 25 BGP: Co n fig u ri n g Pref ix Filters 5. Check that the IP r oute table now cont ains only the other r oute from the neighbor .
BGP: Co n fig u ri n g Ro u te Maps Page 26 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes BGP: Configur ing Route Maps Route maps are ver y pow erful and flexib le entities. Therefore, the configuring of route maps must, b y necessity , be relatively complex.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 27 BGP: Co n fig u ri n g Ro u te Maps Cla u ses There are two types of clauses that can be present in a route.
BGP: Co n fig u ri n g Ro u te Maps Page 28 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Case 1: Case 2: Both of these con f igur ation s would cause outgoing updat e packets with emp ty AS paths to be dropped, and update packet s with an AS path containing 15557 to be allowed.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 29 BGP: Co n fig u ri n g Ro u te Maps Expanded lists use regular expressions to specif y the communities.
BGP: Co n fig u ri n g Ro u te Maps Page 30 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes O n c e y o u h a ve m a d e t h e AC L , a p p l y i t t o t h e m a .
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 31 BGP: Co n fig u ri n g Ro u te Maps Community Comm unity set clauses give y ou a lot of control ov er the commun ity values in updates.
BGP: Co n fig u ri n g Ro u te Maps Page 32 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Atomic- aggregate This adds the atomic aggregate attr ibute to the update .
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 33 BGP: Co n fig u ri n g Ro u te Maps The effect of di ffer e n t comb i n atio n s of cla u ses A map entr y.
BGP: Co n fig u ri n g Ro u te Maps Page 34 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes P ar ticular mention, though, has to be made of the case where the match clause specifies prefix list or A CL as the match cr iter ion, and the route ma p is being applied to outgoing route updates.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 35 BGP: Applyi n g Distrib u te, Path, Pr efix, a n d Ro u te Map Fi lters to a Peer BGP: Applying Distr ib ut.
Examples Page 36 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Examples Example A A ro u te ma p that matches o n a pre fix-list a n d sets the r o u te metrics 1. Create a pref ix list that matches just 52.0 .0.
Codes: C - connected, S - stat ic, R - RIP, B - BGP O - OSPF, IA - OSPF int er area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2 * - candidate default B 45.0.0.0/8 [20/665] via 45.
Examples Page 38 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes Example D Matchi n g o n a n ext-hop prefix-list 1. Create a prefix -list that matche s on the neighbor's IP address: awplus# ship prefix-list nh-test permit 45.
BGP route table Flags: >=Best route for the gi ven prefix, *=Unreachable next hop, W=Withdrawn m=Community, a=Aggregate route, s=Aggregate Suppresse d, D=Damped Learned from: L=Local, e=eBGP Peer, .
Examples Page 40 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes 4. Set the prefix-list to be the match criter io n on a per mit entr y in the route map: route-map com permit 2 match ip address prefix-list test1 If the route 52.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 41 Examples add ip routem=mixed entry=1 match prefixlist=com add ip routem=mixed entry=1 set com=89:89 add ip routem=mixed entry=2 match prefixlist=as add ip routem=mixed entry=2 set aspath=34599 set bgp peer=45.
Examples Page 42 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes With this combination, neither 156.23 .4.32/27 nor 156.34 .4.144/28 appear in the IP route table. The route 15 6.23.4.32/27 is droppe d by the route map f ilter , and the route 156.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 43 Examples Example I Usi n g a n A CL-match i n a ro u te ma p to u pdate j u st a si n gle r o u te o u t of a n u pdate 1. Configure static r outes on the A W+ switch.
BGP route table Flags: >=Best route for th e given prefix, *=Unreachable next hop, W=Withdrawn m=Community, a=Aggregate route, s=Aggregate Suppr essed, D=Damped Learned from: L=Local, e=eBGP Peer, .
W a ys to u se lists i n IP ro u te f ilteri ng f or BGP , with g e n eric co mm a n d exa m ples Path f ilters ip as-path access-list <aslist1> ... ... per m it <re g -ex> ... de n y <re g -ex> ... per m it <re g -ex> ip as-path access-list <aslist2> .
BGP: Applyi n g Ro u te Maps to Imported Ro u tes Page 46 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes BGP: Applying Route Maps to Impor ted Routes The switch is able to impor t routes into BGP that it learnt by non-BGP means.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 47 Other Uses of Ro u te Maps Other Uses of Route Maps Route maps are used in some contexts other than filter ing routes. Let us look br iefly at some of the other contexts in which they are used.
BGP: Ro u te Ma p Filteri n g Example Page 48 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes BGP: Route Map Filter ing Example Here is an example of a set of route maps. BGP co n fig u ratio n Fir st, we need to set the router’ s ASN and the ASN of the peer .
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 49 BGP: Ro u te Map Filter i n g Example set local-preference 9000 route-map outdef permit 3 match ip address .
OSPF: Co n fig u ri n g Ro u te Maps f or Filter i n g a n d Modifyi n g OSPF Ro u tes Page 50 | Use Ro u te Ma ps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes OSPF: Configuring R.
Use Ro u te Maps a n d Other Filters to Filter a n d Alter BGP a n d OSPF Ro u tes | Page 51 OSPF: Co n fig u ri n g Ro u te Maps for Filteri n g a n d Modif yi n g OSPF Ro u tes Exter n al r o u te type The entr y will match all routes of either T ype 1 Exter nal or Ty p e 2 E x t e r n a l .
C613-16128-00 REV E North A m erica Headquarters | 19 8 0 0 N or t h C re e k Par k w ay | S u i te 10 0 | Bot he ll | WA 9 8 01 1 | USA | T: +1 8 0 0 424 42 8 4 | F: + 1 42 5 4 8 1 3 8 95 Asia -Paci .
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il Allied Telesis X908 è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del Allied Telesis X908 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Allied Telesis X908 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Allied Telesis X908 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Allied Telesis X908, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del Allied Telesis X908.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Allied Telesis X908. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Allied Telesis X908 insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
