User manual

Introduction

adapter’s settings), but only for communication between VAX and remote nodes. If your system uses

TOE adapter and you want VAX instance to be able to communicate with the host machine, you will

need either:

• Use dual-homed set-up.

• Or install additional adapter in host machine, such as perhaps USB adapter, that does not use

TOE, and bind XQ to this adapter.

• Or choose to disable TOE mode on the adapter.

Another possible complication can occur with Gigabit Ethernet networks if the use of jumbo frames is

enabled. Gigabit Ethernet networks may use jumbo frames of size exceeding conventional Ethernet’s

1514-byte packet size limit. DEQLA and DEQNA interfaces and OpenVMS VAX software cannot handle

such frames. Therefore VAX MP is unable to communicate with machines that send jumbo frames,

including possibly the host machine itself. If you need to comminicate with those machines using

protocols that do actually utilize large MTU, disable jumbo frame use in your network. Alternatively,

install second adapter in your machine, such as perhaps USB adapter, disable use of outgoing jumbo

frames on this adapter and connect it to the network via a switch that performs translation of incoming

jumbo frames to regular-sized frames, then bind XQ to this adapter. However for protocols that are

configured to use only smaller MTU and only send packets fitting into 1514-byte frame, operating on

mixed-frame network is possible. In particular, TCP can be configured (and in home networks connected

to DSL or cable modem commonly is) to use MTU of 1492 or 1500, rather than large MTU and thus

limiting the size of Ethernet packets with TCP traffic to 1514 bytes.

Terminal emulation

Regular Windows, Linux and OS X console windows provide basic emulation of DEC VT 100 or VT 220

terminals – however a very basic one.

We are not aware of any quality terminal emulators for Linux or OS X. There is a large number of

emulators for Windows however. While we won’t try to list them here, our personal favorite is IVT

VT220 available free for non-secure editions

. One popular commercially available option is Kermit95 by

Columbia University

http://home.planet.nl/~ruurdb/ivt.htm

http://www.columbia.edu/kermit/k95.html