FarSync X.25 for Linux Version 3.5 XOT Runtime FarSite Communications Ltd (www.farsite.com) Release 3.5.6 26th Jul 2021 1. Introduction --------------- The FarSync X.25 family of products for Linux (Version 3.5) is an implementation of X.25 as a collection of Kernel drivers, daemon applications, and supporting utilities. This version of the product provides X.25 over TCP/IP (XOT) and is called the XOT Runtime. This version will allow X.25 applications to make X.25 calls to remote X.25 applications over a TCP network only. Other products in the family provide X.25 support for the FarSite PCI and USB products. 2. Software Installation or Ugrade ---------------------------------- 2.1 Installation ---------------- This release installs for all "Red Hat" like platforms (e.g. RHEL, Fedora Core etc), SuSe, Ubuntu and Debian based distributions. It has been tested with Kernel version from 2.6.10 up to 5.8.0. If you have difficulty installing on other platforms please contact FarSite Support for assistance. If your distro uses a later Kernel version and there appears to be an install issue then please check the support section of our website to see if there are any product updates that may resolve the issue. After you have expanded the fsx25-3.5.x_xot_only.tar.gz archive you should change directory to fsx25-3.5.x and issue the install command as follows: ./install Please see the html documentation on the install CD, or in the doc/ directory for more information about the install process. 2.2 Upgrading an Existing Installation -------------------------------------- If you have version 3.4.2 of the XOT Runtime then you can use just upgrade the software without uninstalling the old version and then installing the new version. This will preserve your configuration and any other changes you may have made to script files etc. Issue the upgrade command as follows: ./upgrade 3. Licensing ------------ After the install process is complete, the product must be licensed within a "grace period", which is 15 days from the time at which the product is installed. The product is fully functional during the grace period, but the XOT lines will cease to operate once the grace period has expired. If you upgraded an alreadyed licensed system, then the product will continue to operate as normal. There is no need to re-activate the license. 4. XOT Devices -------------- The FarSync XOT Runtime software supports XOT over a specially created network device called xot0. The XOT protocol is managed by the fsxotd daemon process, and communicates with the FarSite X.25 daemon through the x25tap driver. When the x25tap driver is loaded it will create the xot0 network device. It is then possible to configure and manage the XOT device with the FarSync Management GUI. At the moment, routes for the XOT lines have to be configured in two places: 1) In the normal way with the "route add -Ax25" command, and 2) with the FarSync Management GUI In the FarSync Management GUI, SVC routes are available through the XOT Routes section, and PVC routes are configured under the XOT tab when the XOT line is selected. 5. Changes ---------- 5.1 Changes since 3.4.2 ----------------------- 1) Support has been added for Kernel up to a least 5.8.x 2) The fsxot daemon has been corrected to not spin while waiting for a connection to establish, or a transmit to complete. 3) As recent Linux distributions have adopted the Consistent Network Device Naming standard (or a variation of it), the licensing utilities have been updated to allow for Ethernet devices that are not called "eth0". 4) The fsx25 daemon has been update to support the new licensing procedures. An enhancement has been made to allow up to 64 x25 lines to be supported. 5) The X.25 API driver has been corrected in several areas: a) listens can now be interrupted successfully. b) The fsx25 driver memory allocation functions have been updated to wait for memory to become available. When memory is fragmented this can avoid calls failing to connect. c) A new example application has been added that demonstrates M-Bit control. d) A new example application has been added that demonstrates mulit-threaded operation. 6) Fixed issue with fsxotd script and pidof confusion where process had same name as script 7) Add support for the presence of /usr/lib/x86_64-linux-gnu folder There have also been a number of documentation enhancements, in the area of manual configuration and new API additions. 5.2 Other Changes ----------------- dependencies on the modprobe.conf file have been removed. 6. Limitations and Known Problems --------------------------------- 1) As a minimum the Kernel version should be 2.6.9 or later. 2) The fsx25admin program has two minor limitations as follows: a) The maximum number of sessions which can be listed in the connections menu is limited to 1024. b) By default, the maximum number of lines that can reported and monitored is 4. This is because each line is viewed as a single adapter of 1 line. This can be changed by setting the adapter/line explicitly with fsx25config, i.e. changing the assignments of adapter/line under the API tab to match the physical port layout. However, if this is done then the FarSite routing feature will not work correctly. 3) When monitoring XOT PVC interfaces the following may appear in the x25 trace: Tx 01 0 0 INFO 2058 Unknown Command=0xf5 This is just some private protocol between the X25 Daemon and the XOT daemon and can be ignored. 4) Under heavy load conditions, the internal buffer in the fsx25mon and fsfmonUdp applications may overrun and therefor report frame loss. 5) It has been noted that under certain circumstances when stopping the XOT Runtime software with the command "/etc/init.d/fshcx25 stop" the x25 driver cannot be unloaded. In this situation a reboot will be required. 6) The support for XOT Keep Alives is limited to just sending the Keep Alive messages. There is no support for incoming XOT Keep Alives. 7) When using XOT loopback testing it has been noted that sometimes using the IPV6 loopback address of ::1, the loopback call cannot be established. This can typically occur on Ubuntu. The problem is thought to be in the underlying networking in the resolution of the IP address. A workaround for this issue is to use "localhost6" instead. 7. Support contacts ------------------- Support information and updates can be found on the FarSite web site at https://farsite.com For general support enquiries: UK Office: email or telephone +44 (0)1256 330461 during normal UK office hours. Comments or queries specifically about this Linux product should be directed to .