SCSI Primary Commands - 2.pdf

More documents

Recommendations

Info

T10/1236-D Revision 20 18 July 2001c) the PERSISTENT RESERVE OUT with CLEAR service action releases persistent reservations andremoves reservation keys for all initiators (see 5.5.3.6.5);d) the TARGET RESET task management function releases reservations established by the reserve/releasemethod and removes all tasks for all logical units in the target and for all initiators (see SAM-2). Persistentreservations remain unmodified;e) the LOGICAL UNIT RESET task management function releases reservations established by the reserve/release method and removes all tasks for all initiators for the addressed logical unit and any logical unitsissuing from it in a hierarchical addressing structure (see SAM-2). Persistent reservations remain unmodified;andf) the CLEAR TASK SET task management function removes all tasks for the selected logical unit for all initiators.Most other logical unit states remain unmodified, including MODE SELECT parameters, reservations,and ACA (see SAM-2).5.7 Removable medium devices with an attached medium changerWhen a logical unit is served by a medium changer, control over one medium transport element may be effectedusing medium changer commands sent to the device server within the logical unit. The level of control is not ascomplete as would be available if a fully functional medium-changer device server were implemented (see SMC).However, the amount of control is sufficient for paired device and medium changer configurations.The device server shall indicate its ability to support medium changer commands by setting the MCHNGR bit to onein its standard INQUIRY data (see 7.3.2). An MCHNGR bit of one shall indicate that the MOVE MEDIUMATTACHED and READ ELEMENT STATUS ATTACHED commands are supported by the device server. Definitionsof the MOVE MEDIUM ATTACHED and READ ELEMENT STATUS ATTACHED commands may be found in SMC.Only one medium transport element shall be permitted, element 0. Only one data transfer element shall bepermitted. Media exchanges shall not be supported by attached medium changers. The RESERVE ELEMENTand RELEASE ELEMENT commands shall not be supported by attached medium changers.38 dpANS SCSI Primary Commands - 2 (SPC-2)
18 July 2001 T10/1236-D Revision 206 Model for processor devicesA SCSI processor device is a primary computing device with the characteristics of a device server, such as apersonal computer, minicomputer, mainframe computer, or auxiliary computing device or server. Such a primarycomputing device is often called a host. The processor device receives or provides packets of data as requestedby an application client.In the SCSI processor device, the device server accepts and provides data packets transferred according tocommands from the application client. An application client and the processor device server are assumed to havea common set of rules by which information is to be exchanged between them, how the information is interpretedby the processor device server, and when it is allowable to exchange the information. These rules are not specifiedby this standard.The application client requests that the processor device server accept a packet of data by transmitting a SENDcommand. The application client requests that the processor device server return a packet of data by transmitting aRECEIVE command. A COPY or EXTENDED COPY command may also be transmitted to the processor deviceserver to request that it serve as a copy manager. The data flow may be between the processor device andanother SCSI device or may be between two SCSI devices under control of the processor device acting as athird-party copy manager.If a processor device server has no resource available to manage a data packet from the application client, has nodata packet to provide to the application client, or has no resources assigned to perform the operation, the deviceserver may choose one of the following responses:a) Terminate the command with CHECK CONDITION status and the sense key NOT READY with the appropriateadditional sense code for the condition. This is the appropriate response to a TEST UNIT READYcommand;b) Delay data transmission until the necessary resource or data packet becomes available;c) Terminate the command with BUSY status; ord) Treat the logical unit as an incorrect logical unit (see SAM-2).A single target may have more than one logical unit. Logical units may serve as additional paths to a singleresource, and/or each logical unit may serve as a path to different resources within the device. A single logical unitmay also serve as a path to multiple resources if the processor device server interprets information within the datapacket and routes the packet to the appropriate resource.If the processor device server determines that an exception condition has occurred while performing an operationspecified by the contents of a data packet, the information describing the condition is returned as a part of a datapacket. If the processor device server determines that an exception condition has occurred while executing theSCSI command from the application client, the command is terminated with a CHECK CONDITION and thefailures are identified through the sense data.Many types of devices may function as processor devices if no other suitable SCSI device type exists and if thepacket exchange protocol specified by the processor device model meets their functional requirements.Processor device types shall not implement element reservations.Reservation restrictions are placed on commands as a result of access qualifiers associated with the type of reservation.The details of which commands are allowed under what types of reservations are described in table 12. Forthe reservation restrictions placed on commands for the reserve/release management method see table 12 column[A]. For the reservation restrictions placed on commands for the persistent reservations management method, seethe columns under [B] in table 12.dpANS SCSI Primary Commands - 2 (SPC-2) 39
Page 1 and 2:
dpANSProjectT10/1236-DRevision 2018
Page 3:
DraftANSI (r)NCITS.351:200xAmerican
Page 6 and 7: T10/1236-D Revision 20 18 July 2001
Page 106 and 107:
T10/1236-D Revision 20 18 July 2001
Page 108 and 109:
Page 110 and 111:
Page 112 and 113:
Page 114 and 115:
Page 116 and 117:
Page 118 and 119:
Page 120 and 121:
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
Page 128 and 129:
Page 130 and 131:
Page 132 and 133:
Page 134 and 135:
Page 136 and 137:
Page 138 and 139:
Page 140 and 141:
Page 142 and 143:
Page 144 and 145:
Page 146 and 147:
Page 148 and 149:
Page 150 and 151:
Page 152 and 153:
Page 154 and 155:
Page 156 and 157:
Page 158 and 159:
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
Page 186 and 187:
Page 188 and 189:
Page 190 and 191:
Page 192 and 193:
Page 194 and 195:
Page 196 and 197:
Page 198 and 199:
Page 200 and 201:
Page 202 and 203:
Page 204 and 205:
Page 206 and 207:
Page 208 and 209:
Page 210 and 211:
Page 212 and 213:
Page 214 and 215:
Page 216 and 217:
Page 218 and 219:
Page 220 and 221:
Page 222 and 223:
Page 224 and 225:
Page 226 and 227:
Page 228 and 229:
Page 230 and 231:
Page 232 and 233:
Page 234 and 235:
Page 236 and 237:
Page 238 and 239:
Page 240 and 241:
Page 242 and 243:
Page 244 and 245:
Page 246 and 247:
Page 248 and 249:
Page 250 and 251:
Page 252 and 253:
Page 254 and 255:
Page 256 and 257:
Page 258 and 259:
Page 260 and 261:
Page 262 and 263:
Page 264 and 265:
Page 266 and 267:
Page 268 and 269:
Page 270 and 271:
Page 272 and 273:
Page 274 and 275:
Page 276 and 277:
Page 278 and 279:
Page 280 and 281:
Page 282 and 283:
Page 284 and 285:
Page 286 and 287:
Page 288 and 289:
Page 290 and 291:
Page 292 and 293:
show all

SCSI Primary Commands - 2.pdf

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?