<- tb8:maintenance:start|Maintenance ^ tb8:maintenance:start|Maintenance Content ^ tb8:maintenance:main_window|Main Window ->
====== Maintenance Window ======

The Maintenance Window is used to do usual maintenance on all DHD devices (e.g., rebooting or updating), get information of system states or for licensing purposes.

[{{ :tb8:maintenance:maintenance_full.png?nolink&600 |//Maintenance Window//}}]
===== Overview =====

The central part of each DHD system is the DSP unit. This can either be operated as stand-alone version or is connected via Ethernet (Series 52) to one or more operating devices.

You can operate several DHD systems together, for example in several studios that are linked via one central router. To simplify the configuration, you can manage multiple devices in one TB8 project.

There are only few limitations for Series 52 devices, because of the ethernet structure.

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**Important**\\  To make the data transfer via UDP work correctly, all devices in the network have to be able to exchange UDP broadcast packets. If this is not possible, for example routers block the UDP traffic, devices can not communicate this way! In this case, ask your system administrator for assistance.
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===== Connecting the Software to the Devices =====

Using the Maintenance software, you can connect the PC with the devices via Ethernet.

In the device list on the left hand side, all devices are shown that are connected with the TB8 PC's Ethernet. You can also connect devices manually via TCP/IP (see [[tb8:maintenance:device#network_config|Network Config]])

The automatic registration works as follows:

Every device transmits automatically a UDP broadcast message once per second via Ethernet that contains the following data:

  * Project ID
  * Device ID
  * Hardware name of the device
  * Name of the device
  * IP Address
  * Serial Number

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**Important**\\  If the PC with the Maintenance software is located in a different network segment than the device, the UDP broadcast messages may not be transferred between the segments. In this case, the automatic registration of devices does not work.

To solve this problem, the transport of UDP messages must be enabled by the network administrator. This is mostly done for certain Ethernet MAC addresses.
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DHD has reserved the MAC address sector 00:0A:63:xx:xx:xx for its products. The last three bytes xx:xx:xx of the MAC address are assigned by DHD during production for every Communication Controller subsequently. At least one Communication Controller must be contained in every device. The MAC address set during production can not be changed later on! Therefore, apart from the identification for the data transfer in a network, it is also used to assign the license codes. (See [[tb8:maintenance:device#enter_license|Enter License]])

Please find further details on the protocols UDP and TCP/IP in the standard literature on computer networks or ask your system administrator.

===== Connecting over Wide Area Networks =====

DHD systems use the TCP/IP protocol for communication of the DSP cores between each other and with the Maintenance PC. In theory, DHD systems could be remote controlled via WAN. Practically, this does not always work correctly. The reasons are the following:

  * Data throughput and latency are often unpredictable in WANs and can change suddenly. This is especially true, if the connection is set up via the open Internet and not via a corporate network.
  * In contrast with a PC, a DHD device is an embedded system, which can also communicate via TCP/IP. But is it not as flexible and tolerant with errors as the PC. In a local network (LAN) with stable conditions, this is not a problem. If the communication is done via WAN though, under certain condition, data can get lost and cause unwanted problems.

Therefore, you should avoid to remote control DHD systems directly via WAN connection.

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**Warning**\\  Do not try to update the firmware via a WAN connection!
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If you have to maintain a remote system anyway, use a remote control software (e.g. TeamViewer or Microsoft Remote Desktop). Use this software to remote control a PC that is located on a local network with the remote system.

In addition, keep the following in mind when working with WAN connections:

  * If less additional traffic is on the line, the data transfer is more stable.
  * If you have the choice, the corporate network or even a special dedicated line is mostly better than the Internet.
  * It might be helpful to connect a remote PC directly than to use a computer network.
  * Please stick to the usual rules for tunneling internal data traffic over public networks (VPN, Access protection, etc.). Ask your system administrator about it.