Micro-HOWTO download a smeserver.iso when your isp keeps disconnecting you.
If you have an unreliable connection to the net, than you might find the following useful. (Do read the information about rsync on the Mitel website first!)
If you do have (even if you do not*) a previous version of the sme server, use that as your seed to start an rsync session. I use the following magic words in my rsync-script. ( putting it in a one-line script beats retyping)
# my download script, filename: download.sh
#
rsync -avv --stats -P --timeout=0 rsync://ftp.e-smith.com/e-smith/e-smith/current/iso/smeserver-5.1.2.iso /mnt/optical/sme512.iso
# end of download script
# usage: sh download.sh
The rsync bit is all one line. My downloaded file is called sme512.iso, use your own names and directories here, and of course, use your local mirror!
The -P is an important change from the standard one on the Mitel website. It stands for '--partial --progress'. Adding it keeps the (a) temporary download file, if the connection is dropped. Adding the --timeout=0 seemed a good idea too, it sets the timeout to infinite.
(note: I'm pretty sure the -P option is responsible for keeping my partially downloaded file. In the past I had an terrible time keeping a partially downloaded file. Every time I would restart rsync it would start at zero bytes, hence the trick with the automagic copying of files, (see below). I'm downloading at the moment, so I'm not going to experiment!)
Sooner or later your connection is dropped. Now DON'T PANIC.
You will find a hidden file in the format .sme512.iso.xxxx in the same directory as you were downloading into, where xxxx is a random string of characters. This extension will be different every time you start a new download session. ( Every time your ISP hangs up, and you reconnect, you get a new IP address. So as far as the Mitel daemon is concerned you are a new user, and you get a new identity. That's why normal ftp clients seldom work (the ones I use anyway), when you try to restart the download, after being disconnected. You are presenting yourself with a new IP address, while trying to download stuff belonging to the old IP address. The daemons on the sending side, rightfully conclude you are an imposter!
Do a:
>mv .sme512.iso.xxxx sme512.iso
If your script is still waiting, ctrl-C it. Restart it, and see, to you amazement, that after a (few)minute(s)or so it will continue where it left off!
Since I am a very suspicious person I also use another little script to make copies of the downloaded bits of file, in case something decides to delete it.
# my tiny copy script rev 0.0.1
cnt=100
while :; do
cp /mnt/optical/.sme512.iso.* /home/smeserver-5.1.2.iso.$cnt
cnt= expr $cnt +1
sleep 600
done
# end of my tiny copy script
Of course you get loads of downloaded files, so you might want to delete the ones you do not need every time your connection is dropped. This is very much a hands on affair, but since I cannot restart the connection automagically, that does not matter to me. Below is an alternative.
# my tiny copy script rev 0.0.2
# this one will keep writing to the same file. If your system crashes you loose all!
while :; do
cp /mnt/optical/.sme512.iso.* /home/smeserver-5.1.2.iso
sleep 600
done
# end of my tiny copy script
As the saying goes, YMMV and I'm sure one day I'll develop have a fully automagical script. Right now, this works, 20 odd interrupts and 74% downloaded!
(*if you have nothing to start with, do:
> touch sme512.iso to create a file without contents.)
I know rsync is not intended to do a download form scratch, but since it works, why worry?
Your comments and/or suggestions are of course always welcome!
kees
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