Ubuntu provides a fairly fool proof way to upgrade from one version to the next but it can take literally hours – when I upgraded my netbook from 9.10 it took just over 4 hours.
The reason for this is that ubuntu’s update-manager downloads everything. What’s worse is if you want to upgrade from a version earlier than 9.10 you must upgrade one release at a time.
Now I’ve got one machine that’s running 8.10, so I’ve got to upgrade to 9.04 first, then 9.10 before I can upgrade to 10.04. If it’s going to take 4 hours a piece then that’s 12 hours at least.
So how can you speed things up if you have either a slow connection or if you have to do multiple upgrades?
Well there’s two ways, the first is to upgrade from scratch – however that’s not viable if you are upgrading a configured machine that gets heavy usage.
The other is to use the alternative iso’s and upgrade from there.
So for that machine running 8.10, I need to download the 9.04, 9.10 and 10.04 alternative iso’s, in this case the for the i386 platform.
Here’s some links to those iso’s:
Now for the upgrade process. Either burn each iso to disk, or mount it locally and run the upgrade.
peter@kodos:~$ sudo mount -o loop ubuntu-9.04-alternate-i386.iso /media/cdrom0
Ubuntu should show the upgrade dialog, however if it doesn’t – or you are doing this over an ssh connection then you can start it manually – just remember to use -Y with the ssh command 😉
peter@kang:~$ ssh -Y kodos peter@kodos:~$ sudo mount -o loop ubuntu-9.04-alternate-i386.iso /media/cdrom0 peter@kodos:~$ gksu "sh /cdrom/cdromupgrade"
You must do this for each step and you can’t skip any of them.
Tip: It will prompt you to check for updates during the procedure. Unless you are upgrading to the latest version, or the intermediate steps (9.04, 9.10 etc) you can safely say no here. This will actually save you a lot of time downloading updates only to wipe them out with the next upgrade.
I found that going from 8.10 to 9.04 took about an hour, but 9.04 to 9.10 just half an hour – a big saving.
Update 2010-05-05: If you are remotely updating a server (i.e. does not have desktop installed) then you can’t use gksu as above. Instead use:
peter@kang:~$ ssh kodos peter@kodos:~$ sudo mount -o loop ubuntu-9.04-alternate-i386.iso /media/cdrom0 peter@kodos:~$ sudo /cdrom/cdromupgrade
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i have the ISO of ubuntu alternate CD. When i want to upgrading my system with that ISO and the method you mentioned above, why its still downloading from internet? Although my modem is disconnected and i choose “No” when the question “Download new update from internet” dialog shown. Do you have the solution?
thank’s a lot
I have noticed that it still does a few downloads.
I’m actually updating a server at the moment (9.04 to 9.10) and I can see it downloading a few updates online with the rest coming from the locally mounted cd. The ones it did download look like security updates rather than package ones.
I’ve just watched the network traffic out on the server I’ve just done the update to and it accessed the network (when I had said no to net access):
* At the start to check for updates
* Any security updates
* A couple of times when updating specific packages (in my case docbook)
* At the end to check for updates for the new version
So I don’t think it would be 100% possible to do an update without some network access – although saying no should mean no.
i’ve just updating my system and there is no more update available, But it’s still have to download around 488MB. But the package that to be fetched is 1759, is that normal? I’ve seen the other person that just fetched 1240 package. Is that my problem?
I’ve now upgraded 7 systems using this technique and I’ve seen different values for this each time.
Depending on what’s been installed on each one, and what platform they started from seems to be a factor.
I don’t have the actual figures but the worst one was around what you’ve seen, but desktop’s tend to have higher downloads than pure servers, but saying no to downloads can help.
Tip: Although in the article I state say no except for the last one (i.e. going to 10.4), say no there as well. You may find it still downloads critical updates, it will be faster. Once complete then run apt-get update, apt-get upgrade – it may reduce that value down.
In fact as updates start to come out (there has already been a few) you may find that as time goes on the amount to download on the last step will increase.
note:
i want to upgrade from 9.10 to 10.04