Nhasi tichatarisa BGP protocol. Isu hatitaure kwenguva yakareba nezvekuti sei uye nei ichishandiswa seyo chete protocol. Kune ruzivo rwakawanda nezvenyaya iyi, semuenzaniso .
Saka chii BGP? BGP is a dynamic routing protocol uye ndiyo yega EGP (External Gateway Protocol) protocol. Iyi protocol inoshandiswa kugadzira nzira paInternet. Ngatitarisei kuti nharaunda inovakwa sei pakati pemarouta maviri eBGP.
Funga nezve nharaunda iri pakati peRouter1 neRouter3. Ngativagadzirise tichishandisa mirairo inotevera:
router bgp 10
network 192.168.12.0
network 192.168.13.0
neighbor 192.168.13.3 remote-as 10
router bgp 10
network 192.168.13.0
network 192.168.24.0
neighbor 192.168.13.1 remote-as 10Muvakidzani mukati meimwe nzira yekuzvimiririra ndeye AS 10. Mushure mekupinda ruzivo pane router, yakadai seRouter1, iyo router inoedza kugadzirisa hukama hwepedyo neRouter3. Mamiriro ekutanga kana pasina chinoitika anodanwa Wamasimba. Kana bgp ichinge yagadziriswa paRouter1, inotanga kuteerera TCP port 179 - ichaenda mudunhu. batanidza, uye painoedza kuvhura chikamu neRouter3, ichapinda mudunhu Active.
Mushure mechikamu chatangwa pakati peRouter1 neRouter3, Vhura mameseji anotsinhaniswa. Kana iyi meseji yatumirwa neRouter1, iyi nyika ichadaidzwa Vhura Sent. Uye kana yagamuchira Vhura meseji kubva kuRouter3, inoenda mudunhu Vhura Confirm. Ngatitarisei zvakanyanya kune iyo Open meseji:
Iyi meseji inopa ruzivo nezve BGP protocol pachayo, iyo router inoshandisa. Nekuchinjanisa Vhura mameseji, Router1 uye Router3 vanotaurirana ruzivo nezvezvirongwa zvavo kune mumwe nemumwe. Aya ma parameter anotevera anopfuudzwa:
- mhando: Izvi zvinosanganisira BGP shanduro iri kushandisa router. Ikozvino shanduro yeBGP ndiyo vhezheni 4 inotsanangurwa muRFC 4271. Vaviri BGP routers vachaedza kutaurirana shanduro inopindirana, kana pane kukanganisa ipapo hakuzovi neBGP sangano.
- AS yangu: izvi zvinosanganisira AS nhamba yeBGP router, ma routers achafanira kubvumirana pane AS nhamba (s) uye inotsanangurawo kana vachange vachimhanya iBGP kana eBGP.
- Bata Nguva: kana BGP isingagamuchire chero keepalive kana kunatsurudza meseji kubva kune rumwe rutivi kwenguva yekubata nguva ipapo ichazivisa rimwe divi 'yakafa' uye ichabvarura chirongwa cheBGP. Nekusagadzika nguva yekubata inoiswa kumasekonzi zana nemakumi masere paCisco IOS routers, meseji yekuchengeta inotumirwa masekonzi makumi matanhatu ega ega. Ma router ese ari maviri anofanirwa kubvumirana pane yekubata nguva kana hapazove neBGP chikamu.
- BGP Identifier: iyi ndiyo yemuno BGP router ID iyo inosarudzwa sezvinoita OSPF:
- Shandisa iyo router-ID iyo yakagadziriswa nemaoko neiyo bgp router-id command.
- Shandisa iyo yepamusoro IP kero pane loopback interface.
- Shandisa iyo yepamusoro IP kero pane yemuviri interface.
- Optional Parameters: pano iwe unowana mamwe maitiro ekusarudza eiyo BGP router. Nzvimbo iyi yawedzerwa kuitira kuti zvinhu zvitsva zviwedzerwe kuBGP pasina kugadzira imwe shanduro.Zvinhu zvaungawana pano ndezvi:
- rutsigiro rweMP-BGP (Multi Protocol BGP).
- rutsigiro rweRoute Refresh.
- rutsigiro rwe4-octet AS nhamba.
Kugadzira nharaunda, zvinotevera zvinofanirwa kusangana:
- Nhamba yeshanduro. Iyo yazvino vhezheni ndeye 4.
- Nhamba yeAS inofanira kufanana nezvawakagadzirisa muvakidzani 192.168.13.3 kure-se10.
- Router ID inofanira kunge yakasiyana nemuvakidzani.
Kana imwe yemiganhu isingagutsi mamiriro aya, router inotumira Notification meseji inoratidza kukanganisa. Mushure mekutumira uye kugamuchira Vhura mameseji, hukama hwevavakidzani hunopinda mudunhu KUSIMBISWA. Mushure meizvi, ma routers anogona kuchinjana ruzivo nezve nzira uye kuita izvi vachishandisa Update mameseji. Iyi ndiyo Yekuvandudza meseji yakatumirwa neRouter1 kuRouter3:
Pano iwe unogona kuona ma network akataurwa neRouter1 uye Path hunhu, iwo anofanana nemametrics. Tichataura nezve Path hunhu mune zvakadzama. Keepalive meseji inotumirwa zvakare mukati mechikamu cheTCP. Iwo anotapurirwa, nekusarudzika, ese makumi matanhatu masekonzi. Iyi ndiyo Keepalive Timer. Kana meseji yeKeepalive ikasagamuchirwa panguva yeHold Timer, izvi zvinoreva kurasikirwa kwekutaurirana nemuvakidzani. By default, akaenzana 60 masekonzi.
Chiratidzo chinobatsira:
Zvinoita sekuti takafunga kuti ma routers anotumira sei ruzivo kune mumwe nemumwe, zvino ngatiedzei kunzwisisa logic yeBGP protocol.
Kushambadzira nzira kuenda kutafura yeBGP, sezviri muIGP protocol, murairo wetiweki unoshandiswa, asi maitiro ekushandisa akasiyana. Kana muIGP, mushure mekutsanangura nzira mumurairo wetiweki, IGP inotarisa kuti ndeapi mainterfaces eiyi subnet uye inoabatanidza mutafura yayo, ipapo murairo wetiweki muBGP unotarisa patafura yekufambisa uye unotarisa. chaizvo inofananidzira nzira mune network network command. Kana zvakadaro zvikawanikwa, nzira idzi dzichaonekwa mutafura yeBGP.
Tarisa nzira muiyo router yezvino IP routing tafura inonyatsoenderana nematanho eiyo network command; kana IP nzira iripo, isa yakaenzana NLRI muBGP tafura yemunharaunda.
Iye zvino ngatisimudze BGP kune vose vakasara uye ona kuti nzira inosarudzwa sei mukati me AS imwe. Mushure mekunge BGP router yagamuchira nzira kubva kumuvakidzani wayo, inotanga kusarudza nzira yakakwana. Pano iwe unofanirwa kunzwisisa kuti ndeupi rudzi rwevavakidzani vanogona kuva - mukati nekunze. Ko router inonzwisisa nekugadzirisa kana muvakidzani akagadzirirwa ari mukati kana kunze? Kana muchikwata:
neighbor 192.168.13.3 remote-as 10 iyo kure-seye parameter inotsanangura AS, iyo inogadziriswa pa router pachayo mu router bgp command 10. Nzira dzinobva mukati me AS dzinoonekwa semukati, uye nzira dzinobva kunze kwe AS dzinoonekwa sekunze. Uye kune imwe neimwe, pfungwa dzakasiyana dzekugamuchira uye kutumira mabasa. Funga nezve iyi topology:
Router imwe neimwe ine loopback interface yakagadzirirwa ip: xxxx 255.255.255.0 - apo x ndiyo nhamba ye router. PaRouter9 tine loopback interface nekero - 9.9.9.9 255.255.255.0. Tichazvizivisa kuburikidza neBGP uye toona kuti inopararira sei. Iyi nzira ichaendeswa kune Router8 uye Router12. Kubva paRouter8, nzira iyi ichaenda kuRouter6, asi kuRouter5 haizove mutafura yekufambisa. Zvakare paRouter12 iyi nzira ichaonekwa patafura, asi paRouter11 haizovepo futi. Ngatiedzei kufunga izvi. Ngatitarisei kuti ndeapi data uye paramita Router9 inotumira kune vavakidzani vayo, ichizivisa nzira iyi. Iyo pakiti pazasi inotumirwa kubva kuRouter9 kuenda kuRouter8.
Ruzivo rwenzira runosanganisira Path hunhu.
Nzira hunhu hwakakamurwa muzvikamu zvina:
- Zvinozivikanwa zvinosungirwa -Ese ma routers anomhanya BGP anofanirwa kuziva aya hunhu. Inofanirwa kunge iripo mune zvese zvigadziriso.
- Inonyatsozivikanwa discretionary -Ese ma routers anomhanya BGP anofanirwa kuziva aya hunhu. Vanogona kunge varipo mune zvigadziriso, asi kuvepo kwavo hakudiwi.
- Optional transitive - inogona kusazivikanwa neese BGP kuita. Kana iyo router isingazive hunhu, inocherekedza iyo yekuvandudza sechikamu uye inoendesa kune vavakidzani vayo, ichichengeta iyo isingazivikanwe hunhu.
- Optional isiri transitive - inogona kusazivikanwa neese BGP kuita. Kana iyo router isingazivi hunhu, ipapo hunhu hunoregeredzwa uye hunoraswa kana hwaendeswa kune vavakidzani.
Mienzaniso yeBGP hunhu:
- Zvinozivikanwa zvinosungirwa:
- Autonomous system nzira
- Next-hop
- mavambo
- Inonyatsozivikanwa discretionary:
- Zvaunoda munharaunda
- Atomic aggregate
- Optional transitive:
- Aggregator
- Communities
- Optional isiri transitive:
- Multi-exit discriminator (MED)
- Muvambi ID
- Cluster list
Muchiitiko ichi, ikozvino tichave tichifarira Origin, Next-hop, AS Path. Sezvo nzira ichipfuura pakati Router8 uye Router9, ndiko kuti, mukati meimwe AS, inoonekwa semukati uye isu tichateerera kune Origin.
Origin hunhu - inoratidza kuti nzira mune yekuvandudza yakawanikwa sei. Zvinogoneka hunhu ukoshi:
- 0 - IGP: NLRI yakagamuchirwa mukati meiyo yekutanga kuzvimiririra system;
- 1 - EGP: NLRI inodzidzwa uchishandisa Exterior Gateway Protocol (EGP). Predecessor kuBGP, isina kushandiswa
- 2 - isina kukwana: NLRI yakadzidziswa neimwe nzira
Muchiitiko chedu, sezvinogona kuonekwa kubva pakiti, yakaenzana ne0. Kana nzira iyi ichiendeswa kuRouter12, iyi code ichava nekodhi ye1.
Zvadaro, Next-hop. Next-hop hunhu
- Iyi ndiyo IP kero yeBGP router iyo nzira yekuenda kune network inoenda.
- Hunhu hunochinja kana prefix yatumirwa kune imwe AS.
Panyaya yeBGP, ndiko kuti, mukati meimwe AS, Next-hop icharatidzwa neakadzidza kana kuudzwa nezve nzira iyi. Muchiitiko chedu, ichava 192.168.89.9. Asi kana nzira iyi yafambiswa kubva paRouter8 kuenda kuRouter6, Router8 inoichinja yoitsiva neyayo. Inotevera-hop ichava 192.168.68.8. Izvi zvinotitungamirira kumitemo miviri:
- Kana router ikaendesa mberi nzira kumuvakidzani wayo wemukati, haichinje Inotevera-hop parameter.
- Kana router ikatumira nzira kune muvakidzani wayo wekunze, inoshandura Next-hop kune ip ye interface kubva iyo router inotumira.
Izvi zvinotitungamira kuti tinzwisise dambudziko rekutanga - Nei kuchave pasina nzira mutafura yenzira paRouter5 uye Router11. Ngatinyatsoongororai. Saka, Router6 yakagamuchira ruzivo nezve nzira 9.9.9.0/24 uye yakabudirira kuiwedzera patafura yenzira:
Router6#show ip route bgp
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
a - application route
+ - replicated route, % - next hop override, p - overrides from PfR
Gateway of last resort is not set
9.0.0.0/24 is subnetted, 1 subnets
B 9.9.9.0 [20/0] via 192.168.68.8, 00:38:25<source>
Π’Π΅ΠΏΠ΅ΡΡ Router6 ΠΏΠ΅ΡΠ΅Π΄Π°Π» ΠΌΠ°ΡΡΡΡΡ Router5 ΠΈ ΠΏΠ΅ΡΠ²ΠΎΠΌΡ ΠΏΡΠ°Π²ΠΈΠ»Ρ Next-hop Π½Π΅ ΠΈΠ·ΠΌΠ΅Π½ΠΈΠ». Π’ΠΎ Π΅ΡΡΡ, Router5 Π΄ΠΎΠ»ΠΆΠ΅Π½ Π΄ΠΎΠ±Π°Π²ΠΈΡΡ <b>9.9.9.0 [20/0] via 192.168.68.8</b> , Π½ΠΎ Ρ Π½Π΅Π³ΠΎ Π½Π΅Ρ ΠΌΠ°ΡΡΡΡΡΠ° Π΄ΠΎ 192.168.68.8 ΠΈ ΠΏΠΎΡΡΠΎΠΌΡ Π΄Π°Π½Π½ΡΠΉ ΠΌΠ°ΡΡΡΡΡ Π΄ΠΎΠ±Π°Π²Π»Π΅Π½ Π½Π΅ Π±ΡΠ΄Π΅Ρ, Ρ
ΠΎΡΡ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΡ ΠΎ Π΄Π°Π½Π½ΠΎΠΌ ΠΌΠ°ΡΡΡΡΡΠ΅ Π±ΡΠ΄Π΅Ρ Ρ
ΡΠ°Π½ΠΈΡΡΡΡ Π² ΡΠ°Π±Π»ΠΈΡΠ΅ BGP:
<source><b>Router5#show ip bgp
BGP table version is 1, local router ID is 5.5.5.5
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter,
x best-external, a additional-path, c RIB-compressed,
Origin codes: i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path
* i 9.9.9.0/24 192.168.68.8 0 100 0 45 i</b>Mamiriro akafanana achaitika pakati peRouter11-Router12. Kuti udzivise mamiriro ezvinhu aya, unofanirwa kugadzirisa Router6 kana Router12, paunenge uchipfuura nzira kuenda kune vavakidzani vemukati, kutsiva yavo IP kero seNext-hop. Izvi zvinoitwa uchishandisa murairo:
neighbor 192.168.56.5 next-hop-selfMushure memurairo uyu, Router6 ichatumira iyo Update meseji, apo ip ye interface Gi0 / 0 Router6 ichatsanangurwa seInotevera-hop yemigwagwa - 192.168.56.6, mushure mokunge iyi nzira ichave yakabatanidzwa mutafura yekufambisa.
Handei mberi tione kana iyi nzira inoonekwa paRouter7 uye Router10. Izvo hazvizove mutafura yekufambisa uye isu tinogona kufunga kuti dambudziko rakafanana nerekutanga neInotevera-hop parameter, asi kana tikatarisa kubuda kweiyo show ip bgp command, tinoona kuti iyo nzira haina kugamuchirwa ipapo kunyangwe neiyo isiriyo Next-hop, zvinoreva kuti nzira yacho haina kana kutapurirana. Uye izvi zvichatitungamira kune kuvepo kweumwe mutemo:
Nzira dzakagamuchirwa kubva kuvakidzani vemukati hadziparidzirwe kune vamwe vavakidzani vemukati.
Sezvo Router5 yakagamuchira nzira kubva kuRouter6, haizopfuudzwa kune mumwe muvakidzani wayo wemukati. Kuti kuchinjisa kuitike, unofanirwa kugadzirisa basa , kana gadzirisa hukama hwakabatana hwevavakidzani (Yakazara Mesh), kureva, Router5-7 munhu wese achave muvakidzani kumunhu wese. Muchiitiko ichi tichashandisa Route Reflector. PaRouter5 unofanira kushandisa murairo uyu:
neighbor 192.168.57.7 route-reflector-clientRoute-Reflector inoshandura maitiro eBGP kana ichipfuura nzira kuenda kumuvakidzani wemukati. Kana muvakidzani wemukati anotsanangurwa se nzira-reflector-client, zvino nzira dzemukati dzichashambadzirwa kune vatengi ava.
Nzira haina kuonekwa paRouter7? Usakanganwa nezve Next-hop zvakare. Mushure mekuita izvi, nzira inofanirawo kuenda kuRouter7, asi izvi hazviitiki. Izvi zvinotisvitsa kune mumwe mutemo:
Iyo inotevera-hop mutemo inongoshanda kune Kunze nzira. Kune nzira dzemukati, iyo inotevera-hop hunhu haina kutsiviwa.
Uye isu tinowana mamiriro ekuti zvakakosha kugadzira nharaunda uchishandisa static routing kana IGP mapuroteni kuzivisa marouters nezvese nzira mukati meAS. Ngatinyorei static nzira paRouter6 uye Router7 uye mushure meizvozvo tichawana nzira yatinoda mutafura ye router. Muna AS 678, tichazviita zvishoma zvakasiyana - isu tichanyoresa static nzira dze 192.168.112.0/24 pa Router10 uye 192.168.110.0/24 pa Router12. Tevere, isu tichagadzira hukama hwemunharaunda pakati peRouter10 neRouter12. Isu tichagadzirisawo Router12 kutumira yayo inotevera-hop kuRouter10:
neighbor 192.168.110.10 next-hop-selfMhedzisiro ichave yekuti Router10 ichagamuchira nzira 9.9.9.0/24, ichagamuchirwa kubva kune ese ari maviri Router7 uye Router12. Ngationei sarudzo inoita Router10:
Router10#show ip bgp
BGP table version is 3, local router ID is 6.6.6.6
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter,
x best-external, a additional-path, c RIB-compressed,
Origin codes: i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found
Network Next Hop Metric LocPrf Weight Path
*>i 9.9.9.0/24 192.168.112.12 0 100 0 45 i
192.168.107.7 0 123 45 i
Sezvatinoona, nzira mbiri uye museve (>) zvinoreva kuti nzira kuburikidza ne192.168.112.12 inosarudzwa.
Ngationei kuti nzira yekusarudza nzira inoshanda sei:
- Nhanho yekutanga kana uchigamuchira nzira ndeyekutarisa kuwanikwa kwayo Inotevera-hop. Ndokusaka, patakagamuchira nzira paRouter5 tisina kuseta Next-hop-yega, nzira iyi haina kuzogadziriswa.
- Zvadaro kunouya Weight parameter. Iyi parameter haisi Path Attribute (PA) uye haina kutumirwa muBGP mameseji. Iyo inogadziriswa munharaunda pane yega yega router uye inongoshandiswa kushandura nzira sarudzo pane iyo router pachayo. Ngatitarisei muenzaniso. Pamusoro apa unogona kuona kuti Router10 yakasarudza nzira ye9.9.9.0/24 via Router12 (192.168.112.12). Kuti uchinje iyo Wieght paramende, unogona kushandisa nzira-mepu kuseta chaiwo nzira, kana kupa huremu kumuvakidzani wayo uchishandisa murairo:
neighbor 192.168.107.7 weight 200Iye zvino nzira dzese kubva kumuvakidzani uyu dzichava nehuremu uhu. Ngationei kuti sarudzo yenzira inoshanduka sei mushure mekunyengera uku:
Router10#show bgp *Mar 2 11:58:13.956: %SYS-5-CONFIG_I: Configured from console by console BGP table version is 2, local router ID is 6.6.6.6 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found Network Next Hop Metric LocPrf Weight Path *> 9.9.9.0/24 192.168.107.7 200 123 45 i * i 192.168.112.12 0 100 0 45 iSezvauri kuona, nzira kuburikidza neRouter7 yasarudzwa, asi izvi hazvizove nemhedzisiro pane mamwe ma router.
- Muchinzvimbo chechitatu tine Local Preference. Iyi parameter iAinozivikanwa discretionary hunhu, izvo zvinoreva kuti kuvepo kwayo isarudzo. Iyi parameter inoshanda chete mukati meAS imwe chete uye inokanganisa sarudzo yenzira chete kune vavakidzani vemukati. Ndokusaka ichifambiswa chete muKugadziridza mameseji akagadzirirwa muvakidzani wemukati. Haipo muKuvandudza mameseji evavakidzani vekunze. Naizvozvo, yakaverengerwa seInozivikanwa discretionary. Ngatiedzei kuishandisa paRouter5. PaRouter5 tinofanira kunge tine nzira mbiri dze9.9.9.0/24 - imwe kuburikidza neRouter6 uye yechipiri kuburikidza neRouter7.
Isu tinotarisa:
Router5#show bgp BGP table version is 2, local router ID is 5.5.5.5 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found Network Next Hop Metric LocPrf Weight Path *>i 9.9.9.0/24 192.168.56.6 0 100 0 45 iAsi sezvatinoona imwe nzira kuburikidza neRouter6. Nzira yekupfuura neRouter7 iripi? Pamwe Router7 haina kana? Ngatitarisei:
Router#show bgp BGP table version is 10, local router ID is 7.7.7.7 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found Network Next Hop Metric LocPrf Weight Path *>i 9.9.9.0/24 192.168.56.6 0 100 0 45 i 192.168.107.10 0 678 45 iZvinoshamisa, zvese zvinoita kunge zvakanaka. Sei isina kuendeswa kuRouter5? Chinhu ndechekuti BGP ine mutemo:
Iyo router inotumira chete idzo nzira dzainoshandisa.
Router7 inoshandisa nzira kuburikidza neRouter5, saka nzira kuburikidza neRouter10 haizofambiswa. Ngatidzokere kune Local Preference. Ngatiise Local Preference paRouter7 uye tione kuti Router5 inoita sei kune izvi:
route-map BGP permit 10 match ip address 10 set local-preference 250 access-list 10 permit any router bgp 123 neighbor 192.168.107.10 route-map BGP in</b>Saka, isu takagadzira nzira-mepu ine nzira dzese uye takaudza Router7 kuti ichinje Local Preference parameter kusvika 250 kana yagamuchirwa, iyo default ndeye 100. Ngationei zvakaitika paRouter5:
Router5#show bgp BGP table version is 8, local router ID is 5.5.5.5 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found Network Next Hop Metric LocPrf Weight Path *>i 9.9.9.0/24 192.168.57.7 0 250 0 678 45 iSezvatinoona ikozvino Router5 inofarira nzira kuburikidza neRouter7. Iwo mufananidzo iwoyo uchange uri paRouter6, kunyangwe zvichimubatsira kuti asarudze nzira kuburikidza neRouter8. Isu tinowedzerawo kuti kuchinja iyi parameter kunoda kutangazve kwenharaunda kuti shanduko iite. Verenga . Takaronga Local Preference. Ngatiendei kune inotevera parameter.
- Sarudze nzira ine Next-hop parameter 0.0.0.0, kureva, nzira dzemunharaunda kana dzakaunganidzwa. Idzi nzira dzinopihwa otomatiki Huremu paramende yakaenzana nehupamhi-32678-mushure mekupinda network network:
Router#show bgp BGP table version is 2, local router ID is 9.9.9.9 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found Network Next Hop Metric LocPrf Weight Path *> 9.9.9.0/24 0.0.0.0 0 32768 i - Ipfupi nzira kuburikidza neAS. Ipfupi AS_Path parameter inosarudzwa. Iwo mashoma maAS nzira inopfuura, zviri nani. Funga nezvenzira inoenda ku9.9.9.0/24 paRouter10:
Router10#show bgp BGP table version is 2, local router ID is 6.6.6.6 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete RPKI validation codes: V valid, I invalid, N Not found Network Next Hop Metric LocPrf Weight Path * 9.9.9.0/24 192.168.107.7 0 123 45 i *>i 192.168.112.12 0 100 0 45 iSezvaunogona kuona, Router10 yakasarudza nzira kuburikidza ne 192.168.112.12 nokuti nzira iyi AS_Path parameter ine 45 chete, uye mune imwe nyaya 123 uye 45. Intuitively clear.
- Iyo inotevera parameter ndeye Origin. IGP (nzira yakawanikwa uchishandisa BGP) iri nani pane EGP (nzira yakawanikwa uchishandisa yakatangira BGP, haichashandiswi), uye EGP iri nani pane isina kukwana? (yakawanikwa neimwe nzira, semuenzaniso nekugovera patsva).
- Iyo inotevera parameter ndeye MED. Isu taive neWieght yaingoshanda munharaunda pane router. Paive neLocal Preference, iyo yaingoshanda mukati meimwe yakazvimirira system. Sezvaungafungidzira, MED iparameter inozofambiswa pakati peanozvimirira masisitimu. Kugona chose nezve iyi parameter.
Hapasisina hunhu huchashandiswa, asi kana nzira mbiri dziine hunhu hwakafanana, ipapo mitemo inotevera inoshandiswa:
- Sarudza nzira kuburikidza nepedyo IGP muvakidzani.
- Sarudza nzira yekare yeBGP nzira.
- Sarudza nzira kuburikidza nemuvakidzani ine diki BGP router ID.
- Sarudza nzira kuburikidza nemuvakidzani ine yakaderera IP kero.
Zvino ngatitarisei nyaya yeBGP convergence.
Ngationei zvinoitika kana Router6 ikarasa nzira 9.9.9.0/24 kuburikidza neRouter9. Ngatibvisei interface Gi0/1 yeRouter6, iyo ichakurumidza kunzwisisa kuti iyo BGP chikamu neRouter8 yakamiswa uye muvakidzani anyangarika, izvo zvinoreva kuti nzira yakagamuchirwa kubva kwairi haina kushanda. Router6 pakarepo inotumira Update mameseji, apo inoratidza inetiweki 9.9.9.0/24 mundima Yakabviswa Nzira. Kana Router5 yangogamuchira meseji yakadaro, inotumira kuRouter7. Asi sezvo Router7 iine nzira kuburikidza neRouter10, inokurumidza kupindura neKugadziridza ine nzira nyowani. Kana zvisingaite kuona kudonha kwemuvakidzani zvichienderana nemamiriro eiyo interface, saka iwe uchafanirwa kumirira iyo Hold Timer kupisa.
Confederation.
Kana iwe uchirangarira, takataura nezve chokwadi chekuti iwe kazhinji unofanirwa kushandisa yakazara yakabatana topology. Nenhamba huru yemarouters mune imwe AS izvi zvinogona kukonzera matambudziko makuru, kuti udzivise izvi unofanirwa kushandisa mubatanidzwa. Imwe AS yakakamurwa kuita akati wandei-AS, iyo inovabvumira kushanda pasina chinodiwa cheiyo topology yakabatana zvizere.
Heino link yeizvi uye gadziriro yeGNS3.
Semuenzaniso, neiyi topology taizofanira kubatanidza marouters ese muAS 2345 kune mumwe nemumwe, asi tichishandisa Confederation, tinogona kumisikidza hukama hwepedyo chete pakati pemarouter akabatana zvakananga kune mumwe nemumwe. Ngatitaurei pamusoro peizvi zvakadzama. Dai isu taingova neAS 2345, saka laForge vagamuchira kufamba kubva Picard waizozviudza kune ma routers Data ΠΈ Worf, asi vaisazoudza router nezvazvo Crusher . Uyewo nzira dzakagoverwa nerouter pachayo laForge, angadai asina kutamiswa Crusher kana Worf-o, kwete Data.
Iwe unozofanirwa kugadzirisa Nzira-Reflector kana hukama hwakakwana hwevavakidzani. Nekukamura imwe AS 2345 kuita 4 sub-AS (2,3,4,5) kune yega yega router, tinopedzisira tave neakasiyana ekushandisa logic. Zvose zvinotsanangurwa zvakakwana .
Sources:
- CCIE Routing uye Kuchinja v5.0 Official Cert Guide, Vhoriyamu 2, Fifth Edition, Narbik Kocharians, Terry Vinson.
- Website
- Website .
Source: www.habr.com