Upgrading EAMs with unreliable Internet connections
If your EAM, DM24SxEAM or *TDE instrument has a slow or intermittent Internet connection, there is a possibility of problems occurring during a firmware upgrade. The system can enter a fault state when an upgrade takes a significantly long time or is interrupted. To guard against this, it is possible to download a mirror copy of the firmware onto the file-system of the EAM itself. It can then upgrade itself using this copy as the upgrade source. The process is essentially identical to using a local mirror site with the exception that it uses the device itself as its own mirror server.
The system should have access to the Internet during the download step but it does not need Internet access while it is actually upgrading. If the download process is interrupted, it can be easily restarted and it will continue from the point at which it failed. The operation of the device is not affected during the download (other than by creating a bandwidth requirement) so this process can be repeated safely and incrementally until it is complete.
Platinum systems use the rsync protocol to update their firmware to the latest revision. rsync is an extraordinarily flexible tool but can be rather complex. The upgrade script on the EAM is a front-end to rsync which is used to hide this complexity and ensure the safe use of the protocol.
Setting up a Platinum system as its own upgrade mirror involves four steps:
- Downloading the mirror content;
- Setting up the system as a local rsync server;
- Configuring the system to use itself as an upgrade server; and
- Safeguarding the upgrade session.
You can then perform the upgrade and, once you are happy that it has been successful, remove the mirror content and return the upgrade system to its standard configuration.
The procedure is slightly different for systems with different architectures so the instructions have been split into three. This set only covers EAMs, DM24SxEAM and *TDE instruments. If you are attempting to upgrade a MkⅡ NAM or Affinity, please select one of the links below:
Downloading the mirror content
The mirror content occupies a significant amount of disk space, so it is important to check the available space before proceeding. To check the space available, log on to the command line of your system and type the command
The output will normally consist of a table with one line of content, such as:
If more than one line is displayed, look for the row where the value in the Mounted on column is "/". The free space is shown in the Available column of the same row. In the example above, it is 321.8 MB
These systems require around 70 MB of free space to store the upgrade image. Only proceed if you have enough space.
Next, enter the following command sequence to download the mirror content.
These commands download the appropriate firmware image from Güralp’s server. If a command fails for any reason, it can be repeated. It causes no harm to repeat a command even if it appears to have succeeded.
The final output from a successful download looks like this (although the numbers may be different):
A repeated download, after a successful download, looks like this (although the numbers may be different):
Problems?
The most common problems experienced at this stage are:
rsync reports “Temporary failure in name resolution”
If you see error messages like
it means that the Domain Name Service (DNS) client is misconfigured. If you are running DHCP, this may be a problem with your DHCP server not providing the address of a name-server (or providing an incorrect one). If you are using static addressing, check and correct the nameserver using the net-setup tool.
rsync reports “Network is unreachable”
If you see error messages like
it means that the network routing is misconfigured. If you are running DHCP, this may be a problem with your DHCP server not providing a default route (or providing an incorrect one). If you are using static addressing, check and correct the default route using the net-setup tool.
rsync reports “rsync error”
If you see error messages like
it means that, most probably, a firewall is blocking traffic on the rsync port. Ask your network administrator to permit the EAM to open TCP connections to host rsync.guralp.com on port 873.
Setting up an rsync server
The rsync server is configured by creating the file /etc/rsyncd.conf using the following commands:
Once the /etc/rsyncd.conf file is in place, you should start the rsync server with the command
Configuring the upgrade system to use the local server
Create the file /etc/conf.d/upgrade.local using the following commands:
Safeguarding the upgrade session.
The system is now ready to be upgraded and the upgrade process will not depend on the internet connection. However, if the command-line session running the upgrade is terminated by a broken connection, that will termnate the upgrade, leaving the system in an undefined state. To guard against this, the upgrade will be run in the screen environment. This creates a protected session which cannot be disconnected. To start the session, enter the commmand
and then key enter again to give you a command-line prompt.
Performing the upgrade
The system can now be updated from the mirror by using the upgrade command. Once the upgrade has completed successfully, the system should be rebooted, either by using the web interface or, from the command-line, with the command reboot.
Tidying up
Once you are totally happy that the upgrade has successful, you can remove the mirror content and return the upgrade system to its normal condition with the commands
Further Reading
rsync is a fascinating and elegant solution to many file transfer problems. Further information is available from the rsync documentation page.
For more information, first contact your local distributor or email .