Brocade Multi-Service IronWare Switching Configuration Gui Instrukcja Użytkownika Strona 547
- Strona / 984
- Spis treści
- BOOKMARKI
Oceniono. / 5. Na podstawie oceny klientów
Multi-Service IronWare Switching Configuration Guide 517
53-1003036-02
Initializing a new ERN
15
• ERN 4 stays in the Pending state, transmits R-APS (NR) messages, and continues to block the
left interface.
FIGURE 129 Initializing an ERP topology - II
Figure 130 shows the next sequence of events. The actions of each ERN are:
• ERN 1 terminates R-APS received on the blocked port, unblocks the non-failed port, stops
transmitting R-APS (NR) messages, and enters the Pending state.
• ERN 2 takes no action.
• ERN 3 takes no action.
• ERN 4 stays in the Pending state and transmits R-APS (NR) messages.
FIGURE 130 Initializing an ERP topology - III
- Multi-Service IronWare 1
- Document History 2
- Contents 3
- Chapter 4 Configuring LLDP 5
- Chapter 7 VLANs 7
- NetIron CER Devices 9
- Brocade NetIron CER 10
- Chapter 17 Topology Groups 16
- Chapter 19 Configuring IP 18
- Chapter 23 sFlow 22
- About This Document 25
- Supported software 26
- Document conventions 27
- Notice to the reader 28
- Related publications 28
- Supported Brocade IP features 31
- Assigning a port name 32
- Modifying port speed 33
- Modifying port mode 34
- Changing the negotiation mode 36
- Modifying port priority (QoS) 37
- Port transition hold timer 37
- Port flap dampening 38
- TABLE 3 link-error-disable 39
- Port loop detection 40
- Enabling loop detection 41
- Clearing loop-detection 42
- Syslog message 43
- Mirroring and Monitoring 44
- ACL-based inbound mirroring 46
- Configuring path trace 51
- Parameter Description 52
- Wait for all cards feature 55
- Link fault signaling 55
- Configuration Examples 56
- Limits and restrictions 62
- TABLE 8 Rx counters 65
- Tx Source Port 66
- Using FDP 69
- Configuring FDP 70
- Displaying FDP information 71
- This line... Displays 72
- Displaying FDP entries 73
- Reading CDP packets 74
- Displaying CDP information 75
- Displaying neighbors 76
- Displaying CDP entries 76
- Clearing CDP information 77
- Syntax: clear fdp table 78
- Syntax: clear fdp counters 78
- Management module switchover 81
- Switchover implications 82
- Brocade(config)# redundancy 83
- Status LED 88
- Software 88
- • show chassis 89
- • show temperature 89
- File system Root directory 90
- Management focus 92
- Flash memory file system 93
- Wildcards 95
- Formatting a flash card 95
- Creating a subdirectory 100
- Brocade# mkdir slot2 TEST 101
- Removing a subdirectory 102
- Renaming a file 102
- 53-1003036-02 103
- Deleting a file 104
- Loading the software 111
- Rebooting from the system 112
- Saving configuration changes 113
- File management messages 114
- Configuring LLDP 115
- General operating principles 116
- LLDP packets 117
- TLV support 117
- Mandatory TLVs 118
- TABLE 21 Port ID subtypes 119
- Configuration considerations 120
- Using LLDP 120
- Configuring transmit mode 121
- Configuring receive mode 121
- Per device 122
- Per port 122
- Syslog messages 123
- General system information 125
- 802.1 capabilities 128
- 802.3 capabilities 129
- • Speed and duplex mode 130
- LLDP configuration summary 131
- Syntax: show lldp 132
- Show lldp statistics 132
- LLDP statistics 133
- LLDP neighbors 134
- LLDP neighbors detail 135
- This field... Displays 136
- Resetting LLDP statistics 137
- Aggregation 139
- LAG formation rules 140
- LAG load sharing 143
- Load sharing for MPLS LAGs 146
- Configuring a LAG 148
- Static LAG Considerations 150
- Creating a keepalive LAG 151
- Configuring load sharing type 152
- Specifying the LAG threshold 153
- Configuring an LACP timeout 154
- Deploying a LAG 155
- Disabling ports within a LAG 156
- Enabling ports within a LAG 157
- Limitations 160
- Displaying LAG information 161
- Example : Wide-Mode Display 163
- TABLE 25 Show LAG information 164
- Displaying LAG statistics 167
- This Field... Displays 171
- Naming a port in a LAG 180
- TABLE 27 Show LAG information 184
- Protocol-based VLANs 196
- VLAN configuration rules 197
- Dual-mode default VLAN 198
- Brocade(config)#vlan 2 200
- Brocade(config-vlan-2)#vlan 1 200
- Configuring port-based VLANs 201
- Example 202
- VLAN groups 206
- Configuring a VLAN group 207
- Configuring aggregated VLANs 211
- Complete CLI examples 212
- Commands for device B 213
- Commands for device C 213
- Commands for device D 214
- Commands for device E 214
- Commands for device F 214
- Configuration rules 216
- Enabling 802.1Q-in-Q tagging 216
- Example configuration 217
- Miscellaneous VLAN features 220
- Brocade(config)# vlan 10 221
- Brocade(config)# vlan 24 223
- Deprecated commands 224
- Existing display command 225
- Displaying VLAN counters 227
- Field Description 228
- IP interface commands 231
- Transparent VLAN flooding 235
- Configuring TVF FID pool size 236
- Transparent firewall mode 237
- Displaying VLAN information 237
- TABLE 36 Output of show vlan 238
- Multi-port static MAC address 242
- Error messages 243
- SA and DA learning and aging 245
- Flooding features 245
- • show vlan tvf-lag-lb 246
- Release Command History 247
- Output field Description 250
- Types of ESI 254
- Creating an ESI 255
- Show VLAN commands 256
- Displaying a single ESI 257
- Tag-type configuration 257
- Displaying tag types 258
- CVLAN translation 260
- CES and Brocade NetIron CER 263
- Configuration steps 265
- Displaying the port type 266
- About IEEE 802.1ad 267
- Display ESI configuration 270
- PB using untagged members 271
- VLANs (SAV) 272
- FIGURE 27 L2PF in a network 273
- FIGURE 28 Physical network 274
- TABLE 41 Port Configuration 274
- Global configuration 275
- Overview 277
- Tag type configuration 281
- 802.1ad at each interface 282
- IEEE 802.1ah configurations 283
- Bind ISID to BVLAN 284
- Bridge (PBB) networks 287
- Displaying port- types 288
- Point to Point PBB 291
- ISID mapping to VPLS 292
- Tag Type and Ether Type 293
- Topology Groups 294
- Show commands 294
- Load balancing traffic 295
- Local switching 297
- Remote switching 298
- End-to-end behavior 298
- PBB 802.1ah 299
- PB 802.1ad 299
- • Duplicates among all 300
- • No duplicates across all 300
- Deleting a VLAN 301
- Deleting an ESI 301
- Default ESI 303
- SVLAN uniqueness 304
- IEEE 802.1ad (PB) 304
- IEEE 802.1ah (PBB) 304
- I-tag uniqueness 305
- Service instance 310
- S-Tagged endpoint 311
- Dual-tagged endpoint 311
- IB-Tagged Endpoint 311
- Customer to ISID mapping 313
- FIGURE 46 S-VLAN keep mode 315
- PBB packet switching 316
- PBB MAC Learning 317
- MAC Learning for PBB Packets 318
- PBB PCP/DEI Setting 319
- B-Tag DEI Setting 320
- I-Tag PCP Setting 320
- S-Tag PCP/DEI Setting 321
- Configuring PBB 322
- Show Commands 325
- 802.1ag over PBB OAM 328
- Configuration scenarios 329
- Types of MEPs and MIPs 331
- 802.1ag for Link MA 332
- 802.1ag for CVLAN and SVLAN 333
- 802.1ag for BVLAN 334
- 802.1ag for ISID 334
- 802.1ag Port Status TLV 335
- 802.1ag RDI 336
- Configuration for CE Devices 337
- Configuration for PE Devices 341
- Brocade# 345
- Enabling or disabling STP 348
- STP in a LAG 350
- Changing STP port parameters 352
- Root Guard 352
- Enabling Root Guard 353
- Checking for Syslog messages 354
- Checking for traps 354
- BPDU Guard 355
- Displaying STP information 358
- SSTP defaults 364
- Displaying SSTP information 365
- SuperSpan™ 366
- BPDU forwarding 367
- Preforwarding state 367
- Configuring SuperSpan 372
- Enabling SuperSpan 373
- STP feature configuration 375
- Fast Uplink Span 377
- Active uplink port failure 378
- PVST or PVST+ compatibility 380
- VLAN Tags and dual mode 381
- Enabling PVST+ support 382
- Configuration examples 383
- Configuring MSTP 386
- Setting the MSTP name 387
- Configuring an MSTP instance 388
- Setting point-to-point link 389
- Disabling MSTP on a port 390
- Enabling MSTP on a device 390
- RTR1 configuration 391
- Core 1 configuration 391
- Core2 configuration 392
- LAN 4 configuration 392
- Displaying MSTP statistics 393
- MSTP support for PBB 399
- Use case scenario 400
- Edge MSTP in a PB network 402
- High availability 403
- Configuring AS-1 404
- Configuring AS-2 404
- Configuring ES-1 405
- Configuring CE-1 and CE-2 406
- CoreMSTP 409
- CS-1 Configuration 410
- Show MSTP 413
- Syntax: show mstp [blocked] 414
- Show mstp region 416
- VLAN configuration 418
- ESI VLAN configuration 420
- Show MSTP detail 421
- Syntax: show mstp detail 422
- Show MSTP detail region 424
- Commands 426
- Assignment of port roles 437
- Ports on Switch 1 438
- Ports on Switch 2 438
- Ports on Switch 3 438
- Ports Switch 4 438
- Point-to-point ports 439
- Bridge port states 440
- State machines 441
- Handshake mechanisms 442
- Proposing and proposed stage 443
- FIGURE 76 Sync stage 444
- FIGURE 77 Synced stage 445
- FIGURE 78 Agree stage 446
- FIGURE 81 Sync and reroot 449
- FIGURE 82 Sync and rerooted 450
- Rerooted, synced, and agreed 451
- Convergence at start up 453
- FIGURE 87 Active Layer 2 path 455
- Configuring RSTP parameters 464
- Brocade(config-vlan-10)# rstp 465
- Brocade(config)# rstp single 465
- Changing port parameters 466
- Syslogs for RSTP 467
- Displaying RSTP information 468
- RSTP support for PB and PBB 473
- Core RSTP 474
- Edge RSTP 474
- Configuration commands 476
- Syntax: show mpls vpls detail 478
- Use case scenarios 479
- Brocade_CE-2(config)#vlan 300 481
- Brocade_CE-1(config)#vlan 300 481
- EdgeRSTP 482
- EdgeRSTP 484
- EdgeRSTP 487
- NetIron CER 489
- Use case 6: Core RSTP 492
- • Forwarding 500
- • Discarding 500
- • Learning 500
- • Disabled 500
- Metro Ring Protocol 503
- Metro Ring Protocol (MRP) 504
- Ring initialization 507
- MRP alarm RHP enhancement 511
- Configuring MRP 516
- Adding an MRP ring to a vlan 517
- Changing the scale timer 518
- MRP Phase 2 519
- Ring interface ownership 521
- Ring interface IDs and types 522
- Normal flow 527
- Flow when a link breaks 529
- Tuning MRP timers 530
- Hello time 531
- Preforwarding time 531
- Effect of the scale timer 532
- Using MRP diagnostics 533
- Displaying MRP information 534
- Displaying ring information 535
- MRP CLI example 537
- Commands on Switch B 538
- Commands on Switch C 539
- Commands on Switch D 539
- Ethernet Ring Protection 541
- ERN roles 542
- ERN interfaces 542
- Protocols 542
- ERP messaging 544
- ERP operational states 544
- ERP timers 545
- Initializing a new ERN 546
- • ERN 2 takes no action 547
- • ERN 3 takes no action 547
- Signal fail 550
- Manual switch 551
- FIGURE 138 MS on Non-RPL node 553
- Forced switch 554
- FIGURE 142 FS clear process 556
- Dual-end blocking 557
- Non-revertive mode 557
- Interconnected rings 557
- FBD flush optimization 559
- Configuring ERP 559
- Device 1 RPL owner 560
- Device 2 RPL node 560
- Device 3 Non-RPL node 560
- Device 4 Non-RPL node 560
- ERP commands 561
- Configuring R-APS MEL value 562
- Configuring interfaces 562
- Device 1 Configuration steps 565
- Device 2 Configuration steps 566
- Configuring dual-end blocking 567
- Configuring the guard timer 567
- Testing the WTR timer 568
- Configuring a hold-off timer 568
- ERP over ESI VLAN 570
- Sample configurations 571
- PBB interconection node (BEB) 572
- ERP support for PBB 573
- Parent ring ID configuration 576
- RAPS-propagate-tc 577
- ERP statistics 579
- Clearing ERP statistics 581
- Layer 2 redundancy 585
- VSRP priority calculation 586
- FIGURE 161 VSRP priority bias 587
- Track ports 588
- Enabling Layer 3 VSRP 590
- Disabling or re-enabling VSRP 591
- Configuring authentication 591
- Configuration considerations: 594
- Displaying VSRP 2 595
- Changing the backup priority 598
- Changing the Hello interval 599
- Changing the Dead interval 600
- Specifying a track port 601
- Displaying VSRP information 602
- VSRP fast start 605
- Configuring VSRP fast start 606
- VSRP slow start 607
- New path established 610
- Master VLAN and member VLANs 612
- Control ports and free ports 612
- Configuring a topology group 613
- • VLAN 2 as master VLAN 614
- • Member VLAN group 2 614
- Brocade MLX series device 616
- • Foundry MRP 619
- Multi-Chassis Trunking (MCT) 621
- How MCT works 622
- MCT components 623
- MCT terminology 624
- Dynamic LAGs 625
- MCT peers 626
- ICL traffic handling 626
- MCT Active-Passive mode 626
- Multicast snooping over MCT 627
- Event MCT-1 MCT-2 628
- L2 protocol packet handling 629
- MCT L2 protocols 629
- MCT feature interaction 630
- Configure MCT 631
- Configure Active-Active MCT 632
- Active-Passive MCT 633
- Configure Active-Passive MCT 633
- PE1 client role 634
- Single level MCT example 635
- Brocade(config-lag-1)# deploy 636
- Cluster Failover Mode 651
- Client isolation mode 651
- Client interfaces delay 651
- Active/Passive mode 652
- Client-role 652
- Keep-alive VLAN 652
- L2 protocol forwarding 653
- MCT switch forwarding action 654
- MCT failover scenarios 656
- Syslogs and debugging 659
- Multicast show commands 662
- MAC operations 663
- Enabling dynamic MAC learning 664
- • Single MAC entry 665
- Cluster Mac types 667
- Clear MAC commands 670
- MCT configuration examples 671
- Client-1: 675
- Client-2: 675
- Single level MCT- extension 676
- Client-3: 680
- Two level MCT example 681
- Router C: 683
- Router D: 684
- MRP integration with MCT 686
- MCT-capable-switch-A 686
- MCT-capable-switch-B: 687
- MCT for VRRP or VRRP-E 689
- Sample MCT Configuration 694
- Support for non-direct ICL 696
- L2VPN timers 697
- Cluster CCP session rules 697
- Handling L2VPN spoke down 698
- Graceful restart support 699
- Sample Configurations 700
- MCT for VPLS 701
- Configuration Considerations 702
- MAC Learning & Synching 704
- MAC Aging 704
- Local switching with MCT 705
- CPU protection with MCT 705
- Auto-discovery with MCT 705
- Cluster-peer verses vpls-peer 705
- Graceful Restart and Upgrade 705
- PE to PE Forwarding 706
- VPLS show commands 707
- MCT for VLL 709
- VLL information sync 710
- Display commands 713
- MCT VLL sample configuration 714
- MCT Snooping 715
- MCT remote CCEP up event 716
- Cluster Peer #2: 720
- MCT Client: 720
- PIM Over MCT 722
- Sending IGMP Queries on CCEPs 723
- Displaying MCT PIM Count 725
- Displaying IGMP Interfaces 726
- Displaying MLD Interfaces 726
- Sample configuration 726
- MCT Peer 2 727
- Configuring IP 729
- • “The IP packet flow” 731
- • “Configuring IP parameters” 731
- The IP packet flow 732
- ARP cache table 733
- Static ARP table 733
- IP route table 734
- IP forwarding cache 735
- IP packet queuing 735
- IP global parameters 736
- Parameter Description Default 737
- IP interface parameters 739
- GRE IP tunnel 741
- Configuring a GRE IP Tunnel 742
- CAM restrictions 743
- Compatible CAM profiles 744
- Configuring a TTL value 746
- Configuring a TOS value 747
- Multicast over GRE tunnel 750
- Operational notes 752
- Clearing the statistics 753
- Switchover behavior 753
- Behavior after an LP failure 754
- Feature scalability 754
- Enabling tunnel statistics 754
- Restart global timers 755
- Configuring IP parameters 757
- IP Unnumbered Interfaces 760
- • Loopback interface 761
- • VE interface 761
- DHCP host subnet selection 764
- Support for other features 764
- • 1 bit copied flag 767
- • 2 bits option class 767
- • 5 bits option number 767
- Defining an IPv4 DNS entry 769
- Using Telnet and Secure Shell 770
- • Ethernet II 771
- Changing the MTU 772
- Globally changing the IP MTU 773
- Changing the router ID 774
- Recalculating the router ID 775
- Configuring ARP parameters 778
- How ARP works 779
- Rate limiting ARP packets 780
- Changing the ARP aging period 781
- Enabling proxy ARP 781
- Enabling local proxy ARP 782
- Creating static ARP entries 783
- Changing the ARP timer 783
- Dynamic ARP inspection 784
- Configuring DAI 785
- Enabling trust on a port 786
- Creating ARP entries 787
- Brocade(config)# vrf vpn1 789
- Adding an ARP entry for a VRF 790
- DHCP snooping 792
- How DHCP snooping works 793
- Configuring DHCP snooping 794
- DHCP snooping suboptions 794
- DHCP option 82 insertion 795
- TABLE 91 Display of show dai 797
- Zero Touch Provisioning 800
- Supported options for DHCP 802
- IP source guard 805
- Enabling IP source guard 806
- IP source guard CAM 807
- Changing the TTL threshold 808
- Disabling ICMP messages 811
- Configuring static routes 813
- Static route types 814
- Static IP route parameters 814
- Configuring a static IP route 816
- Brocade(config)# vrf red 817
- Configuring a “null” route 820
- CAM default route aggregation 821
- Static route configuration 825
- Static route recursive lookup 826
- Naming a static IP route 828
- BFD for Static Routes 831
- Configuring IP load sharing 834
- Administrative distance 835
- Path cost 836
- Masking layer-2 information 839
- How IP load sharing works 845
- Configuring IRDP 846
- Enabling IRDP globally 847
- Filtering Martian addresses 852
- Configuring a IPv6 IP tunnel 854
- FIGURE 205 856
- Example : I-BGP Nexthop 857
- Example : E-BGP Nexthop 857
- Displaying tunnel information 861
- Displaying IP information 863
- Displaying ARP entries 867
- Dual Active Console 871
- Displaying the IP route table 871
- Using the summary option 872
- Using the connected option 873
- Using the static option 873
- Using the longer option 873
- Using the nexthop option 874
- Clearing IP routes 876
- Syntax: show ip traffic 877
- • show ip-tunnels 879
- • show ip-tunnel tunnel ID 879
- Displaying tunnel statistics 881
- Enabling MVRP globally 885
- Enabling MVRP on an interface 886
- MVRP port applicant mode 886
- MVRP port point to point 886
- MVRP interface level timers 887
- MVRP configuration examples 887
- Syslog Messages 893
- Logging control 893
- Clear commands 894
- MMRP networks 895
- Use of MAP context 896
- Sample topology 897
- Declaration of MAC 898
- Configuring MMRP 899
- Enabling MVRP at global level 900
- Per Interface configuration 901
- MMRP interface level timers 902
- CLI Error Messages 906
- Reverse Path Forwarding 907
- RPF configuration 908
- RPF-compatible CAM profiles 909
- Displaying RPF statistics 913
- Displaying RPF logging 915
- • Sample packet flows 917
- Source address 919
- Sampling rate 920
- Configuring sFlow statistics 922
- Specifying the collector 923
- Changing the polling interval 924
- Changing the sampling rate 924
- Enabling sFlow forwarding 927
- ACL-based Inbound sFlow 928
- Brocade(config)# int eth 1/1 930
- Displaying sFlow information 931
- • disabled 932
- • enabled 932
- • IP address 932
- • UDP port 932
- Clearing sFlow statistics 933
- FIGURE 210 UDLD example 937
- Configuring UDLD 938
- Displaying UDLD information 939
- Clearing UDLD statistics 942
- Configuring BFD parameters 945
- Displaying BFD information 946
- Brocade# clear bfd neighbor 950
- Configuring BFD for OSPFv2 951
- Configuring BFD for OSPFv3 952
- Configuring BFD for IS-IS 953
- Configuring BFD for BGP4 954
- Holdover interval 955
- Displaying BFD for BGP4 958
- Displaying BFD applications 959
- BFD for RSVP-TE LSP 962
- BFD session creation 963
- BFD session deletion 964
- BFD session modification 964
- BFD session down handling 964
- Release Command history 967
- • Max LP session exceeded 972
- • Peer session down 972
- • Wait for peer 972
- BFD session down behavior 978
- Brocade(config)# router mpls 979
- • BFD Application Information 980
- • BFD MPLS Information 980
- Syntax: show mpls bfd 983
Powiązane produkty i podręczniki dla Akcesoria komputerowe Brocade Multi-Service IronWare Switching Configuration Gui
Akcesoria komputerowe Brocade 6910 Ethernet Access Switch Configuration Guide (S Instrukcja Użytkownika
(124 strony)
(124 strony)
Akcesoria komputerowe Brocade Multi-Service IronWare Multicast Configuration Gui Instrukcja Użytkownika
(216 strony)
(216 strony)
Akcesoria komputerowe Brocade NetIron CER 2000 Series Hardware Guide (Supporting Instrukcja Użytkownika
(110 strony)
(110 strony)
Akcesoria komputerowe Brocade Multi-Service IronWare Routing Configuration Guide Instrukcja Użytkownika
(846 strony)
(846 strony)
Akcesoria komputerowe Brocade ICX 6610 Stackable Switch Hardware Installation Gu Instrukcja Użytkownika
(108 strony)
(108 strony)
Akcesoria komputerowe Brocade ICX 6450 Stackable Switches Hardware Installation Instrukcja Użytkownika
(116 strony)
(116 strony)
Akcesoria komputerowe Brocade Multi-Service IronWare Administration Guide (Suppo Instrukcja Użytkownika
(432 strony)
(432 strony)
Akcesoria komputerowe Brocade Converged 10GbE Switch Module for IBM BladeCenter Instrukcja Użytkownika
(12 strony)
(12 strony)
Akcesoria komputerowe Brocade ICX 6430-C Compact Switch Hardware Installation Gu Instrukcja Użytkownika
(64 strony)
(64 strony)
Akcesoria komputerowe Brocade ICX 6450-C Compact Switch Hardware Installation Gu Instrukcja Użytkownika
(64 strony)
(64 strony)
Akcesoria komputerowe Brocade Multi-Service IronWare Multiprotocol Label Switch Instrukcja Użytkownika
(852 strony)
(852 strony)
Akcesoria komputerowe Brocade FCoE Switch Module for IBM BladeCenter Installatio Instrukcja Użytkownika
(76 strony)
(76 strony)
Akcesoria komputerowe Brocade FastIron WS Hardware Installation Guide Instrukcja Użytkownika
(74 strony)
(74 strony)
Akcesoria komputerowe Brocade TurboIron 24X Series Hardware Installation Guide Instrukcja Użytkownika
(84 strony)
(84 strony)
Akcesoria komputerowe Brocade FastIron SX Series Chassis Hardware Installation G Instrukcja Użytkownika
(192 strony)
(192 strony)
Akcesoria komputerowe Brocade Access Gateway Administrator's Guide (Support Instrukcja Użytkownika
(0 strony)
(0 strony)
Akcesoria komputerowe Brocade Encryption Switch Hardware Reference Manual (Suppo Instrukcja Użytkownika
(60 strony)
(60 strony)
Akcesoria komputerowe Brocade Encryption Switch QuickStart Guide (Supporting Fab Instrukcja Użytkownika
(20 strony)
(20 strony)
© 2020, manymanuals.pl. Wszelkie prawa zastrzeżone. | 0.155 s |
Manymanuals.com
Manymanuals.de
Manymanuals.fr
Manymanuals.it
Manymanuals.pl
Manymanuals.cz
Manymanuals.es
Manymanuals-pt.com
Komentarze do niniejszej Instrukcji