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Dell Force10 Z9000 FTOS Command Line Reference Guide for the Z9000 System FTOS - Page 714

Link MTU and IP MTU Delta, Tagged Packet

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Command History Usage Information Version 8.3.11.1 Version 8.3.7.0 Version 8.1.1.0 Version 7.5.1.0 pre-Version 6.2.1.0 Introduced on the Z9000. Introduced on the S4810. Introduced on the E-Series ExaScale. Introduced on the C-Series. Introduced on the E-Series. If the packet includes a Layer 2 header, the difference between the link MTU and IP MTU (ip mtu command) must be enough bytes to include the Layer 2 header: • On the C-Series, the IP MTU gets adjusted automatically when the Layer 2 MTU is configured with the mtu command. • On the E-Series, you must compensate for a Layer 2 header when configuring IP MTU and link MTU on an Ethernet interface. Use the ip mtu command. When you enter the no mtu command, FTOS reduces the IP MTU value to 1536 bytes. On the E-Series, to return the IP MTU value to the default, enter no ip mtu. Link MTU and IP MTU considerations for port channels and VLANs are as follows. port channels: • All members must have the same link MTU value and the same IP MTU value. • The port channel link MTU and IP MTU must be less than or equal to the link MTU and IP MTU values configured on the channel members. For example, if the members have a link MTU of 2100 and an IP MTU 2000, the port channel's MTU values cannot be higher than 2100 for link MTU or 2000 bytes for IP MTU. VLANs: • All members of a VLAN must have same IP MTU value. • Members can have different Link MTU values. Tagged members must have a link MTU 4 bytes higher than untagged members to account for the packet tag. • The VLAN link MTU and IP MTU must be less than or equal to the link MTU and IP MTU values configured on the VLAN members. For example, the VLAN contains tagged members with Link MTU of 1522 and IP MTU of 1500 and untagged members with Link MTU of 1518 and IP MTU of 1500. The VLAN's Link MTU cannot be higher than 1518 bytes and its IP MTU cannot be higher than 1500 bytes. The following shows the difference between Link MTU and IP MTU. Layer 2 Overhead Ethernet (untagged) VLAN Tag Untagged Packet with VLAN-Stack Header Tagged Packet with VLAN-Stack Header Link MTU and IP MTU Delta 18 bytes 22 bytes 22 bytes 26 bytes 714

Section	Page
FTOS Command Line Reference Guide for the Z9000 System FTOS 9.1.(0.0)	3
About this Guide	43
Objectives	43
Audience	43
Conventions	43
Information Icons	44
CLI Basics	45
Accessing the Command Line	45
Multiple Configuration Users	45
Object Missing	47
Obtaining Help	47
Using the Keyword no Command	48
Filtering show Commands	49
Command Modes	50
Determining Chassis Mode	56
File Management	57
boot config	57
boot host	59
boot network	59
boot system	60
boot system (S4810 and Z9000)	61
boot system gateway	62
cd	63
change bootflash-image	63
copy	64
copy (Streamline Upgrade)	66
copy running-config startup-config	67
delete	67
dir	68
download alt-boot-image	69
download alt-full-image	69
download alt-system-image	70
format (C-Series and E-Series)	70
format flash (S-Series)	71
format flash (Z9000)	72
fsck flash (S-Series and Z-Series)	72
pwd	73
rename	73
show boot system	74
show bootvar	75
show file	76
show file-systems	77
show linecard	78
show os-version	79
show running-config	80
show startup-config	84
show version	84
upgrade (C-Series version)	87
upgrade (E-Series version)	88
upgrade (S-Series management unit and Z-Series)	90
upgrade fpga-image	92
restore fpga-image	93
upgrade fpga-image	94
Control and Monitoring	97
asf-mode	97
audible cut-off	98
banner exec	98
banner login	99
banner motd	100
cam-audit linecard	101
clear alarms	102
clear command history	102
clear line	103
configure	103
debug cpu-traffic-stats	104
debug ftpserver	105
disable	105
do	106
enable	107
enable optic-info-update interval	107
enable xfp-power-updates	108
end	109
epoch	109
exec-banner	111
exec-timeout	111
exit	112
ftp-server enable	113
ftp-server topdir	114
ftp-server username	114
hostname	115
ip ftp password	116
ip ftp source-interface	116
ip ftp username	118
ip telnet server enable	118
ip telnet source-interface	119
ip tftp source-interface	120
line	121
linecard	122
linecard (4-port 40G line card)	123
module power-off	125
motd-banner	125
ping	126
power-off	129
power-on	130
reload	130
reset	131
rpm <slot> location-led	132
send	133
service timestamps	134
show alarms	135
show chassis	136
show command-history	137
show command-tree	139
show console lp	140
show cpu-traffic-stats	140
show debugging	142
show environment (C-Series and E-Series)	142
show environment (S-Series)	144
show inventory (C-Series and E-Series)	146
show inventory (S-Series and Z-Series)	148
show linecard	150
show linecard boot-information	153
show memory (C-Series and E-Series)	154
show memory (S-Series)	155
show processes cpu (C-Series and E-Series)	156
show processes cpu (S-Series)	158
show processes ipc flow-control	162
show processes memory (C-Series and E-Series)	165
show processes memory (S-Series)	168
show processes switch-utilization	171
show rpm	171
show software ifm	174
show switch links	175
show system (S-Series and Z-Series)	176
show tech-support (C-Series and E-Series)	179
show tech-support (S-Series and Z-Series)	182
ssh-peer-rpm	185
ssh-peer-stack-unit	185
telnet	186
telnet-peer-stack-unit	187
terminal length	187
terminal xml	188
traceroute	189
undebug all	191
upload trace-log	191
virtual-ip	192
write	193
802.1X	195
debug dot1x	196
dot1x auth-fail-vlan	196
dot1x auth-server	197
dot1x auth-type mab-only	197
dot1x authentication (Configuration)	198
dot1x authentication (Interface)	199
dot1x guest-vlan	199
dot1x host-mode	200
dot1x mac-auth-bypass	201
dot1x max-eap-req	201
dot1x max-supplicants	202
dot1x port-control	202
dot1x quiet-period	203
dot1x reauthentication	203
dot1x reauth-max	204
dot1x server-timeout	204
dot1x supplicant-timeout	205
dot1x tx-period	206
show dot1x cos-mapping interface	206
show dot1x interface	207
Access Control Lists (ACL)	211
Commands Common to all ACL Types	211
description	211
remark	212
show config	213
Common IP ACL Commands	214
access-class	214
clear counters ip access-group	214
ip access-group	215
ip control-plane egress-filter	216
show ip accounting access-list	216
Standard IP ACL Commands	218
deny	218
ip access-list standard	220
permit	221
resequence access-list	222
resequence prefix-list ipv4	223
seq	224
Extended IP ACL Commands	226
deny	226
deny arp	228
deny ether-type	230
deny icmp	232
deny tcp	235
deny udp	238
ip access-list extended	240
permit	241
permit arp	243
permit ether-type	245
permit icmp	247
permit tcp	248
permit udp	251
resequence access-list	254
resequence prefix-list ipv4	255
seq arp	255
seq ether-type	257
seq	259
Common MAC Access List Commands	262
clear counters mac access-group	262
mac access-group	263
show mac accounting access-list	264
Standard MAC ACL Commands	265
deny	265
mac access-list standard	266
permit	267
seq	269
Extended MAC ACL Commands	270
deny	270
mac access-list extended	272
permit	273
seq	275
IP Prefix List Commands	276
clear ip prefix-list	276
deny	277
ip prefix-list	278
permit	279
seq	279
show config	280
show ip prefix-list detail	281
show ip prefix-list summary	282
Route Map Commands	283
continue	283
description	284
match as-path	284
match community	285
match interface	286
match ip address	287
match ip next-hop	287
match ip route-source	288
match metric	289
match origin	290
match route-type	290
match tag	291
route-map	292
set as-path	293
set automatic-tag	294
set comm-list delete	294
set community	295
set level	296
set local-preference	297
set metric	298
set metric-type	298
set next-hop	299
set origin	300
set tag	301
set weight	301
show config	302
show route-map	302
AS-Path Commands	303
deny	303
ip as-path access-list	304
permit	305
show config	306
show ip as-path-access-lists	306
IP Community List Commands	307
deny	307
ip community-list	308
permit	309
show config	310
show ip community-lists	310
Bidirectional Forwarding Detection (BFD)	313
bfd all-neighbors	313
bfd disable	314
bfd enable (Configuration)	315
bfd enable (Interface)	315
bfd interval	316
bfd neighbor	317
bfd protocol-liveness	317
clear bfd counters	318
debug bfd	319
ip route bfd	320
isis bfd all-neighbors	321
neighbor bfd	322
neighbor bfd disable	323
show bfd counters	324
show bfd neighbors	325
vrrp bfd	327
Border Gateway Protocol	329
BGP IPv4 Commands	329
address-family	330
aggregate-address	330
bgp add-path	331
bgp always-compare-med	332
bgp asnotation	332
bgp bestpath as-path ignore	333
bgp bestpath as-path multipath-relax	334
bgp bestpath med confed	334
bgp bestpath med missing-as-best	335
bgp bestpath router-id ignore	335
bgp client-to-client reflection	336
bgp cluster-id	336
bgp confederation identifier	337
bgp confederation peers	338
bgp dampening	339
bgp default local-preference	340
bgp enforce-first-as	340
bgp fast-external-fallover	341
bgp four-octet-as-support	341
bgp graceful-restart	342
bgp log-neighbor-changes	343
bgp non-deterministic-med	343
bgp recursive-bgp-next-hop	344
bgp regex-eval-optz-disable	344
bgp router-id	345
bgp soft-reconfig-backup	346
capture bgp-pdu neighbor	347
capture bgp-pdu max-buffer-size	347
clear ip bgp	348
clear ip bgp dampening	349
clear ip bgp flap-statistics	350
clear ip bgp peer-group	351
debug ip bgp	351
debug ip bgp dampening	352
debug ip bgp events	353
debug ip bgp keepalives	353
debug ip bgp notifications	354
debug ip bgp soft-reconfiguration	355
debug ip bgp updates	355
default-metric	356
description	357
distance bgp	357
max-paths	358
neighbor activate	359
neighbor add-path	359
neighbor advertisement-interval	360
neighbor advertisement-start	361
neighbor allowas-in	361
neighbor default-originate	362
neighbor description	362
neighbor distribute-list	363
neighbor ebgp-multihop	364
neighbor fall-over	364
neighbor filter-list	365
neighbor graceful-restart	366
neighbor local-as	367
neighbor maximum-prefix	367
neighbor next-hop-self (C-, E-, and S-Series)	368
neighbor password	369
neighbor peer-group (assigning peers)	370
neighbor peer-group (creating group)	371
neighbor peer-group passive	372
neighbor remote-as	372
neighbor remove-private-as	373
neighbor route-map	374
neighbor route-reflector-client	375
neighbor send-community	375
neighbor shutdown	376
neighbor soft-reconfiguration inbound	377
neighbor subnet	378
neighbor timers	378
neighbor update-source	379
neighbor weight	380
network	380
network backdoor	381
redistribute	382
redistribute isis	383
redistribute ospf	384
router bgp	385
show capture bgp-pdu neighbor	386
show config	387
show ip bgp	387
show ip bgp cluster-list	389
show ip bgp community	390
show ip bgp community-list	392
show ip bgp dampened-paths	394
show ip bgp detail	394
show ip bgp extcommunity-list	396
show ip bgp filter-list	397
show ip bgp flap-statistics	398
show ip bgp inconsistent-as	400
show ip bgp neighbors	401
show ip bgp next-hop	406
show ip bgp paths	407
show ip bgp paths as-path	408
show ip bgp paths community	409
show ip bgp peer-group	410
show ip bgp regexp	412
show ip bgp summary	414
show running-config bgp	416
timers bgp	417
MBGP Commands	417
address family ipv4 multicast (MBGP)	418
aggregate-address	418
bgp dampening	419
clear ip bgp ipv4 multicast	420
clear ip bgp dampening	420
clear ip bgp flap-statistics	421
debug ip bgp dampening	422
debug ip bgp peer-group updates	422
debug ip bgp updates	423
distance bgp	423
neighbor activate	424
neighbor advertisement-interval	425
neighbor default-originate	425
neighbor distribute-list	426
neighbor filter-list	427
neighbor maximum-prefix	427
neighbor next-hop-self	428
neighbor remove-private-as	429
neighbor route-map	429
neighbor route-reflector-client	430
network	430
redistribute	431
redistribute ospf	432
show ip bgp ipv4 multicast	433
show ip bgp cluster-list	434
show ip bgp community	435
show ip bgp community-list	436
show ip bgp dampened-paths	436
show ip bgp filter-list	437
show ip bgp flap-statistics	437
show ip bgp inconsistent-as	438
show ip bgp ipv4 multicast neighbors	439
show ip bgp peer-group	442
show ip bgp summary	442
BGP Extended Communities (RFC 4360)	444
deny	444
deny regex	445
description	446
ip extcommunity-list	446
match extcommunity	447
permit	447
permit regex	448
set extcommunity rt	449
set extcommunity soo	450
show ip bgp ipv4 extcommunity-list	451
show ip bgp paths extcommunity	452
show ip extcommunity-list	452
show running-config extcommunity-list	453
IPv6 BGP Commands	454
address-family	454
aggregate-address	454
bgp always-compare-med	455
bgp bestpath as-path ignore	456
bgp bestpath med confed	456
bgp bestpath med missing-as-best	457
bgp client-to-client reflection	457
bgp cluster-id	458
bgp confederation identifier	458
bgp confederation peers	459
bgp dampening	459
bgp default local-preference	460
bgp enforce-first-as	461
bgp fast-external-fallover	461
bgp four-octet-as-support	462
bgp graceful-restart	462
bgp log-neighbor-changes	463
bgp non-deterministic-med	464
bgp recursive-bgp-next-hop	464
bgp regex-eval-optz-disable	465
bgp router-id	465
capture bgp-pdu neighbor (ipv6)	466
capture bgp-pdu max-buffer-size	466
clear ip bgp * (asterisk)	467
clear ip bgp as-number	468
clear ip bgp ipv6-address	469
clear ip bgp peer-group	470
debug ip bgp ipv6 dampening	470
clear ip bgp ipv6 flap-statistics	471
debug ip bgp	472
debug ip bgp ipv6 dampening	472
debug ip bgp events	473
debug ip bgp keepalives	474
debug ip bgp notifications	474
debug ip bgp updates	475
default-metric	476
description	476
distance bgp	477
ipv6 prefix-list	477
max-paths	478
maximum-paths	479
neighbor activate	479
neighbor advertisement-interval	480
neighbor allowas-in	480
neighbor default-originate	481
neighbor description	482
neighbor distribute-list	482
neighbor ebgp-multihop	483
neighbor fall-over	484
neighbor filter-list	484
neighbor maximum-prefix	485
neighbor X:X:X::X password	486
neighbor next-hop-self	486
neighbor peer-group (assigning peers)	487
neighbor peer-group (creating group)	488
neighbor peer-group passive	488
neighbor remote-as	489
neighbor remove-private-as	490
neighbor route-map	490
neighbor route-reflector-client	491
neighbor shutdown	492
neighbor subnet	492
neighbor timers	493
neighbor update-source	494
neighbor weight	494
network	495
network backdoor	496
redistribute	497
redistribute isis	498
redistribute ospf	499
router bgp	499
show capture bgp-pdu neighbor	500

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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
1,450
1,451
1,452
1,453
1,454
1,455
1,456
1,457
1,458
1,459
1,460
1,461
1,462
1,463
1,464
1,465
1,466
1,467
1,468
1,469
1,470
1,471
1,472
1,473
1,474
1,475
1,476
1,477
1,478
1,479
1,480
1,481
1,482
1,483

Match case Limit results 1 per page

Command History

Version 8.3.11.1

Introduced on the Z9000.

Version 8.3.7.0

Introduced on the S4810.

Version 8.1.1.0

Introduced on the E-Series ExaScale.

Version 7.5.1.0

Introduced on the C-Series.

pre-Version

6.2.1.0

Introduced on the E-Series.

Usage

Information

If the packet includes a Layer 2 header, the difference between the link MTU and IP MTU (

mtu

command) must be enough bytes to include the Layer 2 header:

•

On the C-Series, the IP MTU gets adjusted automatically when the Layer 2 MTU is

configured with the

mtu

command.

•

On the E-Series, you must compensate for a Layer 2 header when configuring IP MTU

and link MTU on an Ethernet interface. Use the

ip mtu

command.

When you enter the

no mtu

command, FTOS reduces the IP MTU value to 1536 bytes. On the

E-Series, to return the IP MTU value to the default, enter

no ip mtu

Link MTU and IP MTU considerations for port channels and VLANs are as follows.

port channels:

•

All members must have the same link MTU value and the same IP MTU value.

•

The port channel link MTU and IP MTU must be less than or equal to the link MTU and

IP MTU values configured on the channel members. For example, if the members have

a link MTU of 2100 and an IP MTU 2000, the port channel’s MTU values cannot be

higher than 2100 for link MTU or 2000 bytes for IP MTU.

VLANs:

•

All members of a VLAN must have same IP MTU value.

•

Members can have different Link MTU values. Tagged members must have a link MTU

4 bytes higher than untagged members to account for the packet tag.

•

The VLAN link MTU and IP MTU must be less than or equal to the link MTU and IP MTU

values configured on the VLAN members. For example, the VLAN contains tagged

members with Link MTU of 1522 and IP MTU of 1500 and untagged members with Link

MTU of 1518 and IP MTU of 1500. The VLAN’s Link MTU cannot be higher than 1518

bytes and its IP MTU cannot be higher than 1500 bytes.

The following shows the difference between Link MTU and IP MTU.

Layer 2 Overhead

Link MTU and IP MTU Delta

Ethernet (untagged)

18 bytes

VLAN Tag

22 bytes

Untagged Packet

with VLAN-Stack

Header

22 bytes

Tagged Packet with

VLAN-Stack Header

26 bytes

714