Upgrading EAMs with unreliable Internet connections

If your EAM, DM24SxEAM or *TDE instrument has a slow or intermittant Internet connection, there is a possibility of problems ocurring 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 filesystem 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
• Performing the upgrade.

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:

• Instructions for MkⅡ NAMs
• Instructions for Affinities

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

df -h

The output will normally consist of a table with one line of content, such as:

EAM1234 ~ # df -h
Filesystem                Size      Used Available Use% Mounted on
/dev/root               512.0M    190.3M    321.8M  37% /
EAM1234 ~

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.

mkdir /home/Pt-firmware-mirror.local
cd /home/Pt-firmware-mirror.local
GSLSRC=rsync.guralp.com/platinum-stable/CMG-DCM-mk4-eabi
rsync -EgHloprtv --exclude resolv.conf rsync://$GSLSRC .

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):

⋮
CMG-DCM-mk4-eabi/var/spool/recdata/.keep
CMG-DCM-mk4-eabi/var/spool/to-rdisk/
CMG-DCM-mk4-eabi/var/spool/to-rdisk/.keep
CMG-DCM-mk4-eabi/var/tmp/
CMG-DCM-mk4-eabi/var/tmp/.keep

sent 52,768 bytes  received 91,126,040 bytes  6,753,985.78 bytes/sec
total size is 90,933,054  speedup is 1.00
EAM1234 ~ #

A repeated download, after a successful download, looks like this (although the numbers may be different):

EAM1234 ~ # rsync -EgHloprtv --exclude resolv.conf rsync://$GSLSRC .
receiving incremental file list

sent 418 bytes  received 74,456 bytes  49,916.00 bytes/sec
total size is 90,933,054  speedup is 1,214.48
EAM1234 ~ #

Problems?

The most common problems experienced at this stage are:

rsync: getaddrinfo: rsync.guralp.com 873: Temporary failure in name resolution
	rsync error: error in socket IO (code 10) at clientserver.c(122) [receiver=3.0.2]

rsync: failed to connect to rsync.guralp.com: Network is unreachable (101)
	rsync error: error in socket IO (code 10) at clientserver.c(122) [receiver=3.0.2]

rsync error: received SIGINT, SIGTERM or SIGHUP (code 20) at rsync.c(541)

Setting up an rsync server

The rsync server is configured by creating the file /etc/rsyncd.conf using the following commands:

cat >/etc/rsyncd.conf <<EOF
port = 61616
[platinum-local-mirror]
path = /home/Pt-firmware-mirror.local
comment = Platinum firmware
numeric ids = yes
log file = /var/log/rsync.log
timeout = 600
hosts allow = *
EOF

Once the /etc/rsyncd.conf file is in place, you should start the rsync server with the command

rsync --daemon

Configuring the upgrade system to use the local server

Create the file /etc/conf.d/upgrade.local using the following commands:

cat >/etc/conf.d/upgrade.local <<EOF
RSYNC_HOST="localhost"
RSYNC_PORT="61616"
RSYNC_MODULE="platinum-local-mirror"
RSYNC_ADDITIONAL_OPTS="--no-delay-updates --delete-during"
EOF

Perform the upgrade

The system can now be updated from the mirror by using the upgrade command.

Further Reading

rsync is a fascinating and elegant solution to many file transfer problems. Further information is available from the rsync documentation page.