Hello, Naoned. Could you try to specify a snapshot using --toSnapshot with snapshot id? The id is shown in diskutil apfs list. I think the system volume is mounted on a snapshot. In my environment, disk2s5s1 is snapshot. it has correct seal and mount on '/'. $ diskutil list apfs ...    +-> Volume disk2s5 D75FFE69-60AA-4C51-A3DE-52B1753DA61D          APFS Volume Disk (Role):  disk2s5 (System)     Name:           sysapfs (Case-insensitive)     Mount Point:        /Users/username/mnt     Capacity Consumed:     15121588224 B (15.1 GB)     Sealed:          Broken     FileVault:         No (Encrypted at rest)     |     Snapshot:         5891FB51-B637-4CC6-8EEF-959D961167C8     Snapshot Disk:       disk2s5s1     Snapshot Mount Point:   /     Snapshot Sealed:      Yes In addition, Bombich Software (they makes Carbon Copy Cloner) also face a same obstacle, and they're working with Apple.

Thank you,  sl149q. What do you mean the result from SetInterfaceEnable? According to a document (https://developer.apple.com/documentation/networkingdriverkit/iousernetworkethernet), we have to override the SetInterfaceEnable on a custom class that we define, and then the function called by system, I think. Also, GetMaxTransferUnit. My code for these functions are following. ... kern_return_t IMPL(nictest, SetInterfaceEnable) {   if(isEnable)   {     log("SetInterfaceEnable method is called [isEnable == true] : Return kIOReturnSuccess");   }   else   {     log("SetInterfaceEnable method is called [isEnable == false] : Return kIOReturnSuccess");   }   return kIOReturnSuccess; } ... kern_return_t IMPL(nictest, GetMaxTransferUnit) {   log("GetMaxTransferUnit method is called : return kIOReturnSuccess");   *mtu = 1500;   return kIOReturnSuccess; } ... Thanks.

I'm also trying to make a network device driver using NetworkingDriverKit. It seems to success a making queues, but I couldn't found any packet transmissions by my driver. Logs of my driver in initialization as following.   default 10:29:43.107556+0900  kernel Found class: nictest   default 10:29:43.109040+0900  kernel init method is called   default 10:29:43.109380+0900  kernel Hello World at start   default 10:29:43.114891+0900  kernel net dext: IOUserNetworkPacketBufferPool::Create(this, "pool", packet_count, buffer_count, buffer_size, &pool);   default 10:29:43.115073+0900  kernel net dext: IOUserNetworkTxSubmissionQueue::Create(pool, this, packet_count, 0, dispatch_queue, &tx_sub_queue);   default 10:29:43.115077+0900  kernel net dext: sub_queue->CopyDataQueue(&ivars->tx_sub_dsource)   default 10:29:43.115098+0900  kernel net dext: CreateActionTxSubAvailable(sizeof (void*), &ivars->tx_sub_action);   default 10:29:43.115107+0900  kernel net dext: ivars->tx_sub_dsource->SetDataAvailableHandler(ivars->tx_sub_action);   default 10:29:43.115112+0900  kernel net dext: ivars->tx_sub_dsource->SetEnable(true);   default 10:29:43.115119+0900  kernel net dext: tx_sub_queue->SetEnable(true)   default 10:29:43.115226+0900  kernel net dext: IOUserNetworkTxCompletionQueue::Create(pool, this, packet_count, 0, dispatch_queue, &com_queue);   default 10:29:43.115230+0900  kernel net dext: tx_com_queue->CopyDataQueue(&ivars->tx_com_dsource);   default 10:29:43.115247+0900  kernel net dext: CreateActionTxComDataServiced(sizeof (void*), &ivars->tx_com_action);   default 10:29:43.115251+0900  kernel net dext: ivars->tx_com_dsource->SetDataAvailableHandler(ivars->tx_com_action);   default 10:29:43.115253+0900  kernel net dext: ivars->tx_com_dsource->SetEnable(true);   default 10:29:43.115257+0900  kernel net dext: tx_com_queue->SetEnable(true);   default 10:29:43.115381+0900  kernel net dext: IOUserNetworkRxSubmissionQueue::Create(pool, this, packet_count, 0, dispatch_queue, &rx_sub_queue);   default 10:29:43.115385+0900  kernel net dext: rx_sub_queue->CopyDataQueue(&ivars->rx_sub_dsource);   default 10:29:43.115401+0900  kernel net dext: CreateActionRxSubAvailable(sizeof (void*), &ivars->rx_sub_action);   default 10:29:43.115406+0900  kernel net dext: ivars->rx_sub_dsource->SetDataAvailableHandler(ivars->rx_sub_action);   default 10:29:43.115408+0900  kernel net dext: ivars->rx_sub_dsource->SetEnable(true);   default 10:29:43.115416+0900  kernel net dext: rx_sub_queue->SetEnable(true);   default 10:29:43.115709+0900  kernel net dext: IOUserNetworkRxCompletionQueue::Create(pool, this, packet_count, 0, dispatch_queue, &rx_com_queue);   default 10:29:43.115712+0900  kernel net dext: com_queue->CopyDataQueue(&ivars->rx_sub_dsource);   default 10:29:43.115729+0900  kernel net dext: CreateActionRxComDataServiced(sizeof (void*), &ivars->rx_com_action);   default 10:29:43.115739+0900  kernel net dext: ivars->rx_sub_dsource->SetDataServicedHandler(ivars->rx_com_action);   default 10:29:43.115741+0900  kernel net dext: ivars->rx_sub_dsource->SetEnable(true);   default 10:29:43.115746+0900  kernel net dext: rx_com_queue->SetEnable(true);   default 10:29:43.115776+0900  kernel net dext: const IOUserNetworkMediaType types[] = {    kIOUserNetworkMediaEthernetAuto,    kIOUserNetworkMediaEthernetNone,    kIOUserNetworkMediaEthernet1000BaseT | kIOUserNetworkMediaOptionFullDuplex  };   default 10:29:43.115778+0900  kernel net dext: ret = ReportAvailableMediaTypes(types, 3);   default 10:29:43.115806+0900  kernel net dext: ReportLinkStatus(kIOUserNetworkLinkStatusInactive, kIOUserNetworkMediaEthernetNone);   default 10:29:43.115832+0900  kernel net dext: RegisterEthernetInterface(macAddress, pool, ivars->queues, 4);   default 10:29:43.142245+0900  kernel net dext: GetMaxTransferUnit methos is called   default 10:29:43.143402+0900  kernel net dext: SetInterfaceEnable method is called [isEnable == true]   default 10:29:43.143810+0900  kernel net dext: SetInterfaceEnable method is called [isEnable == false] I'm not sure why this driver is disabled after enabled. Do you have any solution for it? Thank you.