Home » Dell Manuals » Hubs & Switches » Dell S3100 » Manual Viewer

Dell S3100 Command Line Reference Guide for the Series 9.100.0 - Page 322

bgp enforce-first-as, bgp fast-external-fallover

Add to My Manuals
Save this manual to your list of manuals

Page 322 highlights

This is done under BGP configuration and is supported per address family - for IPv4 and IPv6 address families. The configuration for a particular address family applies across all VRFs configured. This command must be performed on the router which is attaching link bandwidth to prefixes (typically a border router) as well as the router which is expected to load share traffic proportional to the bandwidth of the external links. bgp enforce-first-as Disable (or enable) enforce-first-as check for updates received from EBGP peers. Syntax bgp enforce-first-as To turn off the default, use the no bgp enforce-first-as command. Defaults Enabled Command Modes ROUTER BGP Command History This guide is platform-specific. For command information about other platforms, see the relevant Dell Networking OS Command Line Reference Guide. Version Description 9.8(2.0) 9.8(0.0P5) 9.8(0.0P2) 9.7(0.0) 9.0.2.0 8.3.19.0 8.3.11.1 8.3.7.0 7.8.1.0 7.7.1.0 7.4.1.0 Introduced on the S3100 series. Introduced on the S4048-ON. Introduced on the S3048-ON. Introduced on the S6000-ON. Introduced on the S6000. Introduced on the S4820T. Introduced on the Z9000. Introduced on the S4810. Introduced on the S-Series. Introduced on the C-Series. Introduced. Usage Information This command is enabled by default, that is for all updates received from EBGP peers, BGP ensures that the first AS of the first AS segment is always the AS of the peer. If not, the update is dropped and a counter is increments. Use the show ip bgp neighbors command to view the "failed enforce-first-as check" counter. If you disable the enforce-first-as command, it can be viewed using the show ip protocols command. In the event of an enfore-first-as check failure, the existing BGP session is flapped. Related Commands • show ip bgp neighbors - view the information the BGP neighbors exchange. • show ip protocols - view information on routing protocols. bgp fast-external-fallover Enable the fast external fallover feature, which immediately resets the BGP session if a link to a directly connected external peer fails. Syntax bgp fast-external-fallover To disable fast external fallover, use the no bgp fast-external-fallover command. Defaults Enabled Command Modes ROUTER BGP 322 Border Gateway Protocol

Section	Page
Dell Command Line Reference Guide for the S3100 Series 9.10(0.0)	3
About this Guide	38
Objectives	38
Audience	38
Conventions	38
CLI Basics	39
Accessing the Command Line	39
Multiple Configuration Users	39
Obtaining Help	40
Navigating the CLI	41
Using the Keyword no Command	42
Filtering show Commands	42
Enabling Software Features on Devices Using a Command Option	42
feature vrf	43
show feature	43
Command Modes	44
File Management	52
boot system	52
cd	53
copy	54
delete	56
dir	57
format	58
fsck flash	59
mkdir	59
mount nfs	60
rmdir	60
upgrade system	61
rename	62
restore factory-defaults	63
show boot system	65
show bootvar	66
show file-systems	67
show os-version	68
show running-config	69
show startup-config	72
show version	73
upgrade	75
Control and Monitoring	77
banner exec	77
banner login	78
banner motd	79
cam-acl	80
cam-acl-vlan	81
clear line	82
configure	83
disable	83
do	84
enable	85
enable optic-info-update interval	86
end	87
exec-timeout	87
exit	88
ftp-server enable	89
ftp-server topdir	90
ftp-server username	91
hostname	92
ip http source-interface	92
ip http vrf	93
ip ftp password	94
ip ftp source-interface	95
ip ftp username	96
ip ftp vrf	96
ip telnet server enable	97
ip telnet server vrf	97
ip telnet source-interface	98
ip telnet vrf	99
ip tftp source-interface	100
ip tftp vrf	100
line	101
login concurrent-session	102
login statistics	103
motd-banner	105
ping	105
reload	108
send	109
service timestamps	109
show alarms	110
show cam-acl-vlan	111
show command-history	112
show cpu-traffic-stats	113
show debugging	114
show environment	115
show inventory	116
show login statistics	118
show memory	120
show processes cpu	121
show processes ipc flow-control	123
show processes memory	125
show software ifm	127
show system	128
show tech-support	131
ssh-peer-stack-unit	134
telnet	134
telnet-peer-stack-unit	136
terminal length	136
traceroute	137
undebug all	139
virtual-ip	139
write	140
802.1ag	142
ccm disable	142
ccm transmit-interval	143
clear ethernet cfm traceroute-cache	143
database hold-time	144
disable	144
domain	144
ethernet cfm	145
ethernet cfm mep	145
ethernet cfm mip	146
mep cross-check	146
mep cross-check enable	147
mep cross-check start-delay	147
ping ethernet	148
show ethernet cfm domain	148
show ethernet cfm maintenance-points local	149
show ethernet cfm maintenance-points remote	150
show ethernet cfm mipbd	151
show ethernet cfm statistics	151
show ethernet cfm port-statistics	152
show ethernet cfm traceroute-cache	153
service	153
traceroute cache hold-time	154
traceroute cache size	154
traceroute ethernet	155
802.1X	156
dot1x critical-vlan	157
debug dot1x	158
dot1x auth-fail-vlan	158
dot1x auth-server	159
dot1x auth-type mab-only	160
dot1x authentication (Configuration)	160
dot1x authentication (Interface)	161
dot1x guest-vlan	162
dot1x host-mode	163
dot1x mac-auth-bypass	163
dot1x max-eap-req	164
dot1x max-supplicants	165
dot1x port-control	165
dot1x profile	166
dot1x quiet-period	167
dot1x reauthentication	167
dot1x reauth-max	168
dot1x server-timeout	169
dot1x static-mab	170
dot1x supplicant-timeout	171
dot1x tx-period	171
mac	172
show dot1x cos-mapping interface	173
show dot1x interface	174
show dot1x profile	176
Access Control Lists (ACL)	177
Commands Common to all ACL Types	178
remark	178
show config	179
Common IP ACL Commands	180
access-class	180
clear counters ip access-group	181
ip access-group	182
ip control-plane egress-filter	183
show ip accounting access-list	183
show ip access-lists	185
Standard IP ACL Commands	185
deny	186
ip access-list standard	187
permit	188
resequence access-list	189
seq	190
Extended IP ACL Commands	191
deny	191
deny icmp	193
deny tcp	194
deny udp	197
ip access-list extended	199
permit	200
permit tcp	201
permit udp	203
resequence access-list	205
seq	206
Common MAC Access List Commands	208
clear counters mac access-group	208
mac access-group	209
show mac access-lists	210
show mac accounting access-list	211
Standard MAC ACL Commands	212
deny	212
mac access-list standard	213
permit	214
seq	215
Extended MAC ACL Commands	217
deny	217
mac access-list extended	218
permit	219
IP Prefix List Commands	221
clear ip prefix-list	221
deny	222
ip prefix-list	223
seq	223
show config	224
show ip prefix-list detail	225
show ip prefix-list summary	226
Route Map Commands	227
continue	227
description	228
match as-path	228
match community	229
match interface	230
match ip address	231
match ip next-hop	232
match ip route-source	233
match metric	233
match origin	234
match route-type	235
match tag	236
route-map	237
set as-path	238
set automatic-tag	238
set comm-list delete	239
set community	240
set level	241
set local-preference	242
set metric	243
set metric-type	244
set next-hop	244
set origin	245
set tag	246
set weight	247
show config	247
show route-map	248
AS-Path Commands	249
ip as-path access-list	249
show ip as-path-access-lists	250
IP Community List Commands	250
ip community-list	250
show ip community-lists	251
deny (for Standard IP ACLs)	252
deny (for Extended IP ACLs)	253
seq (for Standard IPv4 ACLs)	254
deny tcp (for Extended IP ACLs)	255
deny udp (for Extended IP ACLs)	256
deny arp (for Extended MAC ACLs)	257
deny icmp (for Extended IP ACLs)	258
deny ether-type (for Extended MAC ACLs)	259
deny (for Standard MAC ACLs)	260
deny (for Extended MAC ACLs)	262
permit (for Standard IP ACLs)	263
permit arp (for Extended MAC ACLs)	264
permit ether-type (for Extended MAC ACLs)	265
permit icmp (for Extended IP ACLs)	266
permit udp (for Extended IP ACLs)	267
permit (for Extended IP ACLs)	268
permit (for Standard MAC ACLs)	270
seq (for Standard MAC ACLs)	271
permit tcp (for Extended IP ACLs)	272
seq arp (for Extended MAC ACLs)	273
seq ether-type (for Extended MAC ACLs)	274
seq (for IP ACLs)	275
seq (for IPv6 ACLs)	276
permit udp (for IPv6 ACLs)	277
permit tcp (for IPv6 ACLs)	278
permit icmp (for IPv6 ACLs)	280
permit (for IPv6 ACLs)	281
deny udp (for IPv6 ACLs)	282
deny tcp (for IPv6 ACLs)	283
deny icmp (for Extended IPv6 ACLs)	284
deny (for IPv6 ACLs)	285
Access Control List (ACL) VLAN Groups and Content Addressable Memory (CAM)	287
member vlan	287
ip access-group	287
show acl-vlan-group	288
show cam-acl-vlan	289
cam-acl-vlan	290
show cam-usage	291
show running config acl-vlan-group	293
acl-vlan-group	293
show acl-vlan-group detail	294
description (ACL VLAN Group)	295
Bidirectional Forwarding Detection (BFD)	296
bfd all-neighbors	296
bfd disable	297
bfd enable (Configuration)	298
bfd enable (Interface)	298
bfd interval	299
bfd neighbor	300
bfd protocol-liveness	300
ip route bfd	301
ipv6 ospf bfd all-neighbors	302
isis bfd all-neighbors	303
neighbor bfd	304
neighbor bfd disable	304
show bfd neighbors	305
vrrp bfd neighbor	307
Border Gateway Protocol	308
BGP IPv4 Commands	308
address-family	308
aggregate-address	309
bgp add-path	310
bgp always-compare-med	311
bgp asnotation	312
bgp bestpath as-path ignore	313
bgp bestpath as-path multipath-relax	313
bgp bestpath med confed	314
bgp bestpath med missing-as-best	314
bgp bestpath router-id ignore	315
bgp client-to-client reflection	316
bgp cluster-id	316
bgp confederation identifier	317
bgp confederation peers	318
bgp connection-retry-timer	319
bgp dampening	319
bgp default local-preference	320
bgp dmzlink-bw	321
bgp enforce-first-as	322
bgp fast-external-fallover	322
bgp four-octet-as-support	323
bgp graceful-restart	324
bgp non-deterministic-med	325
bgp recursive-bgp-next-hop	325
bgp regex-eval-optz-disable	326
bgp router-id	327
clear ip bgp	328
clear ip bgp dampening	329
clear ip bgp flap-statistics	330
clear ip bgp peer-group	331
deny bandwidth	332
debug ip bgp	333
debug ip bgp dampening	334
debug ip bgp events	335
debug ip bgp keepalives	336
debug ip bgp notifications	336
debug ip bgp soft-reconfiguration	337
debug ip bgp updates	338
default-metric	339
description	340
maximum-paths	340
neighbor activate	341
neighbor add-path	342
neighbor advertisement-interval	343
neighbor advertisement-start	343
neighbor allowas-in	344
neighbor default-originate	345
neighbor description	346
neighbor distribute-list	346
neighbor ebgp-multihop	347
neighbor fall-over	348
neighbor local-as	349
neighbor maximum-prefix	350
neighbor password	351
neighbor peer-group (assigning peers)	352
neighbor peer-group (creating group)	353
neighbor peer-group passive	354
neighbor remote-as	354
neighbor remove-private-as	355
neighbor route-map	356
neighbor route-reflector-client	357
neighbor sender-side-loopdetect	358
neighbor send-community	359
neighbor shutdown	360
neighbor soft-reconfiguration inbound	360
neighbor timers	361
neighbor update-source	362
neighbor weight	363
network	364
network backdoor	365
permit bandwidth	366
redistribute	366
redistribute ospf	367
router bgp	368
set extcommunity bandwidth	369
show capture bgp-pdu neighbor	370
show config	371
show ip bgp	371
show ip bgp cluster-list	373
show ip bgp community	374
show ip bgp community-list	376
show ip bgp dampened-paths	378
show ip bgp detail	379
show ip bgp extcommunity-list	380
show ip bgp filter-list	381
show ip bgp flap-statistics	383
show ip bgp inconsistent-as	384
show ip bgp neighbors	386
show ip bgp next-hop	389
show ip bgp paths	390
show ip bgp paths community	391
show ip bgp peer-group	392
show ip bgp regexp	394
show ip bgp summary	395
show running-config bgp	397
timers bgp	398
MBGP Commands	399
debug ip bgp dampening	399
distance bgp	400
show ip bgp dampened-paths	401
BGP Extended Communities (RFC 4360)	402
set extcommunity rt	402
set extcommunity soo	403
show ip bgp paths extcommunity	404
show ip extcommunity-list	405
IPv6 BGP Commands	405
clear ip bgp ipv6 unicast soft	405
debug ip bgp ipv6 unicast soft-reconfiguration	406
ipv6 prefix-list	407
neighbor soft-reconfiguration inbound	407
show ipv6 prefix-list	408
IPv6 MBGP Commands	409
show ipv6 mbgproutes	409
Content Addressable Memory (CAM)	410
CAM Profile Commands	410
cam-acl (Configuration)	411
cam-acl-egress	413
cam-optimization	414
show cam-acl	414
test cam-usage	416
Control Plane Policing (CoPP)	418
control-plane-cpuqos	418
service-policy rate-limit-cpu-queues	418
service-policy rate-limit-protocols	419
ip unknown-unicast	420
ipv6 unknown-unicast	420
show cpu-queue rate cp	421
show ip protocol-queue-mapping	422
show ipv6 protocol-queue-mapping	422
show mac protocol-queue-mapping	423
Debugging and Diagnostics	425
Diagnostics and Monitoring Commands	425
logging coredump stack-unit	425
Offline Diagnostic Commands	426
diag stack-unit	426
offline stack-unit	427
online stack-unit	428
Hardware Commands	428
clear hardware stack-unit	428
clear hardware system-flow	429
clear hardware vlan-counters	430
hardware watchdog	430
show hardware mac	431
show hardware ip	431
show hardware stack-unit	432
show hardware buffer interface	440
show hardware counters interface	441
show hardware buffer-stats-snapshot	442
show hardware stack-unit buffer-stats-snapshot (Total Buffer Information)	443
show hardware system-flow	445
show hardware vlan-counters	447
show hardware drops	447
Dynamic Host Configuration Protocol (DHCP)	450
Commands to Configure the System to be a DHCP Server	450
clear ip dhcp	450
debug ip dhcp server	451
debug ipv6 dhcp	451
default-router	452
disable	452
dns-server	453
domain-name	453
excluded-address	454
hardware-address	455
host	455
lease	456
netbios-name-server	456
netbios-node-type	457
network	458
pool	458
show ip dhcp binding	459
show ip dhcp configuration	459
show ip dhcp conflict	460
show ip dhcp server	461
Commands to Configure Secure DHCP	461
arp inspection	461
arp inspection-trust	462
clear ip dhcp snooping	462
clear ipv6 dhcp snooping binding	464
ip dhcp relay	464
ip dhcp snooping	465
ipv6 dhcp snooping	465
ipv6 dhcp snooping vlan	466
ip dhcp snooping binding	466
IPv6 DHCP Snooping Binding	467
ip dhcp snooping database	468
ipv6 dhcp snooping database write-delay	468
ip dhcp snooping database renew	469
ipv6 dhcp snooping database renew	469
ip dhcp snooping trust	470
ipv6 dhcp snooping trust	470
ip dhcp source-address-validation	471
ip dhcp relay information-option	472
ip dhcp snooping verify mac-address	472
ipv6 dhcp snooping verify mac-address	473
ip helper-address	473
ipv6 helper-address	474
show ip dhcp snooping	474
show ipv6 dhcp snooping	477
Commands to Configure DNS	477
ip name-server	477
ip domain-name	478
ip domain-list	479
ip host	479
clear host	480
Equal Cost Multi-Path (ECMP)	481
ecmp-group	481

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1,000
1,001
1,002
1,003
1,004
1,005
1,006
1,007
1,008
1,009
1,010
1,011
1,012
1,013
1,014
1,015
1,016
1,017
1,018
1,019
1,020
1,021
1,022
1,023
1,024
1,025
1,026
1,027
1,028
1,029
1,030
1,031
1,032
1,033
1,034
1,035
1,036
1,037
1,038
1,039
1,040
1,041
1,042
1,043
1,044
1,045
1,046
1,047
1,048
1,049
1,050
1,051
1,052
1,053
1,054
1,055
1,056
1,057
1,058
1,059
1,060
1,061
1,062
1,063
1,064
1,065
1,066
1,067
1,068
1,069
1,070
1,071
1,072
1,073
1,074
1,075
1,076
1,077
1,078
1,079
1,080
1,081
1,082
1,083
1,084
1,085
1,086
1,087
1,088
1,089
1,090
1,091
1,092
1,093
1,094
1,095
1,096
1,097
1,098
1,099
1,100
1,101
1,102
1,103
1,104
1,105
1,106
1,107
1,108
1,109
1,110
1,111
1,112
1,113
1,114
1,115
1,116
1,117
1,118
1,119
1,120
1,121
1,122
1,123
1,124
1,125
1,126
1,127
1,128
1,129
1,130
1,131
1,132
1,133
1,134
1,135
1,136
1,137
1,138
1,139
1,140
1,141
1,142
1,143
1,144
1,145
1,146
1,147
1,148
1,149
1,150
1,151
1,152
1,153
1,154
1,155
1,156
1,157
1,158
1,159
1,160
1,161
1,162
1,163
1,164
1,165
1,166
1,167
1,168
1,169
1,170
1,171
1,172
1,173
1,174
1,175
1,176
1,177
1,178
1,179
1,180
1,181
1,182
1,183
1,184
1,185
1,186
1,187
1,188
1,189
1,190
1,191
1,192
1,193
1,194
1,195
1,196
1,197
1,198
1,199
1,200
1,201
1,202
1,203
1,204
1,205
1,206
1,207
1,208
1,209
1,210
1,211
1,212
1,213
1,214
1,215
1,216
1,217
1,218
1,219
1,220
1,221
1,222
1,223
1,224
1,225
1,226
1,227
1,228
1,229
1,230
1,231
1,232
1,233
1,234
1,235
1,236
1,237
1,238
1,239
1,240
1,241
1,242
1,243
1,244
1,245
1,246
1,247
1,248
1,249
1,250
1,251
1,252
1,253
1,254
1,255
1,256
1,257
1,258
1,259
1,260
1,261
1,262
1,263
1,264
1,265
1,266
1,267
1,268
1,269
1,270
1,271
1,272
1,273
1,274
1,275
1,276
1,277
1,278
1,279
1,280
1,281
1,282
1,283
1,284
1,285
1,286
1,287
1,288
1,289
1,290
1,291
1,292
1,293
1,294
1,295
1,296
1,297
1,298
1,299
1,300
1,301
1,302
1,303
1,304
1,305
1,306
1,307
1,308
1,309
1,310
1,311
1,312
1,313
1,314
1,315
1,316
1,317
1,318
1,319
1,320
1,321
1,322
1,323
1,324
1,325
1,326
1,327
1,328
1,329
1,330
1,331
1,332
1,333
1,334
1,335
1,336
1,337
1,338
1,339
1,340
1,341
1,342
1,343
1,344
1,345
1,346
1,347
1,348
1,349
1,350
1,351
1,352
1,353
1,354
1,355
1,356
1,357
1,358
1,359
1,360
1,361
1,362
1,363
1,364
1,365
1,366
1,367
1,368
1,369
1,370
1,371
1,372
1,373
1,374
1,375
1,376
1,377
1,378
1,379
1,380
1,381
1,382
1,383
1,384
1,385
1,386
1,387
1,388
1,389
1,390
1,391
1,392
1,393
1,394
1,395
1,396
1,397
1,398
1,399
1,400
1,401
1,402
1,403
1,404
1,405
1,406
1,407
1,408
1,409
1,410
1,411
1,412
1,413
1,414
1,415
1,416
1,417
1,418
1,419
1,420
1,421
1,422
1,423
1,424
1,425
1,426
1,427
1,428
1,429
1,430
1,431
1,432
1,433
1,434
1,435
1,436
1,437
1,438
1,439
1,440
1,441
1,442
1,443
1,444
1,445
1,446
1,447
1,448
1,449

Match case Limit results 1 per page

This is done under BGP configuration and is supported per address family – for IPv4 and IPv6 address families.

The configuration for a particular address family applies across all VRFs configured.

This command must be performed on the router which is attaching link bandwidth to prefixes (typically a border

router) as well as the router which is expected to load share traffic proportional to the bandwidth of the external

links.

bgp enforce-first-as

Disable (or enable) enforce-first-as check for updates received from EBGP peers.

Syntax

bgp enforce-first-as

To turn off the default, use the

no bgp enforce-first-as

command.

Defaults

Enabled

Command Modes

ROUTER BGP

Command History

This guide is platform-specific. For command information about other platforms, see the relevant

Dell Networking

OS Command Line Reference Guide

Version

Description

9.8(2.0)

Introduced on the S3100 series.

9.8(0.0P5)

Introduced on the S4048-ON.

9.8(0.0P2)

Introduced on the S3048-ON.

9.7(0.0)

Introduced on the S6000–ON.

9.0.2.0

Introduced on the S6000.

8.3.19.0

Introduced on the S4820T.

8.3.11.1

Introduced on the Z9000.

8.3.7.0

Introduced on the S4810.

7.8.1.0

Introduced on the S-Series.

7.7.1.0

Introduced on the C-Series.

7.4.1.0

Introduced.

Usage Information

This command is enabled by default, that is for all updates received from EBGP peers, BGP ensures that the first

AS of the first AS segment is always the AS of the peer. If not, the update is dropped and a counter is increments.

Use the

show ip bgp neighbors

command to view the “failed enforce-first-as check” counter.

If you disable the

enforce-first-as

command, it can be viewed using the

show ip protocols

command.

In the event of an enfore-first-as check failure, the existing BGP session is flapped.

Commands

•

show ip bgp neighbors

— view the information the BGP neighbors exchange.

•

show ip protocols

— view information on routing protocols.

bgp fast-external-fallover

Enable the fast external fallover feature, which immediately resets the BGP session if a link to a directly connected external peer fails.

Syntax

bgp fast-external-fallover

To disable fast external fallover, use the

no bgp fast-external-fallover

command.

Defaults

Enabled

Command Modes

ROUTER BGP

322

Border Gateway Protocol