Update libssh2 to 1.7 or higher on Lamp Stack 14

I'm sure that I wrote a reply to this yesterday, but I must have forgot to hit "save"...! Doh! Anyway...

Debian Jessie (the basis of v14.x) will only be supported for another ~8 months (June 2020). So migrating/upgrading is something that you're going to need to consider within the next few months anyway (and I wouldn't recommend that you leave it too late). So now seems as good a time as any to do that.

Migrating/Upgrading to v15.x/Debian 9/Stretch will give you libssh2 v1.7.0 for "free" too! :)

Although perhaps if you could give me a better understanding on what you are running on LAMP and what your general requirements are, plus why you need a newer version of libssh2 I could give more specific suggestion/advice.

Regardless, here is some general info on the potential pathways to migrate/upgrade. There are 2 potential pathways. Both have pros and cons.

The first is to do a "normal" Debian "in place" upgrade - essentially that is upgrading your current system to a Debian 9/Stretch base. It's how most Debian systems are upgraded and will likely go fairly smoothly (although there is always chance of hiccups). That will install newer versions of most of your packages (including TurnKey ones) although there may be some tweaks that we've applied to our v15.x servers that you won't get (as Debian tends to have pretty sane defaults, I wouldn't expect that you'd be missing anything super important though).

Unfortunately, i haven't had a chance to explicitly document this for TurnKey (I've started, but haven't finished and currently have some high priority items I need to get onto). But if you have a google you will likely find some tutorials that will be appropriate (you're upgrading from "Debian 8/Jessie" (the basis of v14.x) to "Debian 9/Stretch" (the basis of v15.x). Debian themselves provide quite extensive documentation which is worth at least a skim through.

The alternative is to use TKLBAM to migrate your current data to a new v15.x server. That will mean you start afresh on a new v15.x server, but with your current data in place. There is a high chance that you will need to adjust some settings to get everything working smoothly, but as the changes between v14.x and v15.x aren't as dramatic as previous versions (e.g. v13.x to v14.x) there shouldn't be many big headaches. It's possibly a little more work (at least in comparison to an "in place" upgrade which goes smoothly) but the final result should be good. This option isn't explicitly documented either, although the TKLBAM: Migration to v14.x from earlier versions of TurnKey Linux page covers the general gist of it and other than the specific software notes (towards the end) should be a reasonable rundown of the process.

The major upside with using TKLBAM to migrate is that your current server can stay "as is" until you are sure the new one is ready, then you can swap across the DNS records to the new server (or switch the elastic IP if you're using one) and destroy the current server once you're sure all is well.

If you go with #1 ("inplace" Debian upgrade), then I strongly suggest that you take a full snapshot (aka "clone") of your current system so you can rollback if things go badly. TKLBAM is a great backup tool, but will likely require you to move on to the second option if things go pear shaped and you don't have some sort of snapshot/clone.

As noted, if you go with #2 (migration via TKLBAM) this server stays as is. So a current TKLBAM backup is all you need.

I'm happy to assist as best I can, but either way it'll be a fairly substantial job and I may not be able to give you "blow by blow" support in a super timely manner.

Your call... But either way, please feel free to ask further questions or let me know if you get stuck and need a hand. I'll aim to write up some docs soon, but I can't promise that will be super soon.

Hi Jeremy,

thanks a lot for your fast response. Yes, I know upgrade to the v15 is a possibility. But I installed many small tools and changed many configurations, so this would be a bigger job and I want to wait a little bit more for this upgrade.

I need the newer libssh2 version to connect to ssh-servers over php. Some newer servers disable some key exchange methods, so the connection with php failed.

The very simple php command:

ssh2_connect('sftp.server.com', 22);

failed with the error message:

"Unable to exchange encryption keys"

This causes on an older libssh2 version. But thanks for your help. I'm just looking for an other possibility to connect to these servers.

Bye Gunnar