HP 8/80 Fabric OS Administrator's Guide v6.4.0 (53-1001763-01, June 2010) - Page 120

Lossless core, Configuring Lossless Dynamic Load Sharing

Page 120 highlights

4 Lossless Dynamic Load Sharing on ports TABLE 9 Policy Combinations of routing policy and IOD with Lossless DLS enabled (Continued) IOD Rebalance result with Lossless DLS enabled Exchange-based Disabled Exchange-based Enabled No frame loss, but out of order frames may occur. No frame loss and no out of order frames. Topology restrictions apply. Intended for FICON environment. Lossless core Lossless core works with the default configuration of the Brocade DCX and DCX-4S to prevent frame loss during a core blade removal and insertion. This feature is on by default and cannot be disabled. Lossless core has the following limitations: • Only supported with IOD disabled which means Lossless core cannot guarantee in-order delivery of exchanges. • ICL limitations. • Traffic flow limitations. ICL Limitations If ICL ports are connected during a core blade removal, then it is equivalent to removing external E_Ports which cause I/O disruption on the ICL ports that have been removed. If ICL ports are connected during a core blade insertion, then it is equivalent to adding external E_Ports which may cause I/O disruption due to reroutes. Lossless DLS, if enabled, takes effect to prevent I/O disruption. Traffic flow limitations The FA4-18 and FR4-18i AP blades, which are supported on the Brocade DCX and DCX-4S, may continue to experience frame drops after core blade removal or insertion. The path between an FC10-6, FA4-18, and FR4-18i blade and an FX8-24 blade, or vice-versa, will experience I/O disruption because the FC10-6, FA4-18, and FR4-18i blades do not support this feature. Configuring Lossless Dynamic Load Sharing You configure Lossless DLS switch- or chassis-wide by using the dlsSet command to specify that no frames are dropped while rebalancing or rerouting traffic. 1. Connect to the switch and log in using an account assigned to the admin role. 2. Enter the appropriate dlsSet command to enable or disable Lossless Dynamic Load Sharing. switch:admin>dlsset --enable lossLess switch:admin>dlsset --disable lossLess Lossless Dynamic Load Sharing in Virtual Fabrics Enabling Lossless Dynamic Load Sharing is optional on logical switches in a Virtual Fabric. If you enable this feature, it must be on a per logical switch basis and can affect other logical switches in the fabric.XISL use must be disabled for Lossless DLS to be enabled 80 Fabric OS Administrator's Guide 53-1001763-01

  • 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

80
Fabric OS Administrator’s Guide
53-1001763-01
Lossless Dynamic Load Sharing on ports
4
Lossless core
Lossless core works with the default configuration of the Brocade DCX and DCX-4S to prevent
frame loss during a core blade removal and insertion. This feature is on by default and cannot be
disabled. Lossless core has the following limitations:
Only supported with IOD disabled which means Lossless core cannot guarantee in-order
delivery of exchanges.
ICL limitations.
Traffic flow limitations.
ICL Limitations
If ICL ports are connected during a core blade removal, then it is equivalent to removing external
E_Ports which cause I/O disruption on the ICL ports that have been removed.
If ICL ports are connected during a core blade insertion, then it is equivalent to adding external
E_Ports which may cause I/O disruption due to reroutes. Lossless DLS, if enabled, takes effect to
prevent I/O disruption.
Traffic flow limitations
The FA4-18 and FR4-18i
AP blades, which are supported on the Brocade DCX and DCX-4S, may
continue to experience frame drops after core blade removal or insertion. The path between an
FC10-6, FA4-18, and FR4-18i blade and an FX8-24 blade, or vice-versa, will experience I/O
disruption because the FC10-6, FA4-18, and FR4-18i blades do not support this feature.
Configuring Lossless Dynamic Load Sharing
You configure Lossless DLS switch- or chassis-wide by using the
dlsSet
command to specify that no
frames are dropped while rebalancing or rerouting traffic.
1.
Connect to the switch and log in using an account assigned to the admin role.
2.
Enter the appropriate
dlsSet
command to enable or disable Lossless Dynamic Load Sharing.
switch:admin>
dlsset --enable lossLess
switch:admin>
dlsset --disable lossLess
Lossless Dynamic Load Sharing in Virtual Fabrics
Enabling Lossless Dynamic Load Sharing is optional on logical switches in a Virtual Fabric. If you
enable this feature, it must be on a per logical switch basis and can affect other logical switches in
the fabric.XISL use must be disabled for Lossless DLS to be enabled
Exchange-based
Disabled
No frame loss, but out of order frames may occur.
Exchange-based
Enabled
No frame loss and no out of order frames. Topology restrictions apply. Intended
for FICON environment.
TABLE 9
Combinations of routing policy and IOD with Lossless DLS enabled
(Continued)
Policy
IOD
Rebalance result with Lossless DLS enabled