Wait for server to be available (work/home local networks)

[Moritz Maisel]

I tested deja dup (13.7-0ubuntu0karmic1 from ppa on ubuntu karmic) in two setups: Backup to a NAS (via smb) and to a local firewire-drive.

I configured deja dup to run daily but I don't have my backup target always available (disk not plugged in / NAS offline).

The problem in poth setups is, that deja dup just tries to do the backup without first checking the availability of the target: It does the preparing of the backup and then throws an error when failing to access the target to write the backup.

What about checking the availability of the target (even before doing the preparing to save resources) and in case of the target not being writeable, ask the user to either schedule the backup to a later moment or have her/him plug in the disk / switch on the NAS?

Thanks for your work!

[Michael Terry (mterry)]

Thanks for the bug! We check and delay the backup if you're not online, but not if the target is not readable/writable. That's a good idea though.

[Michael Terry (mterry)]

A proposal from question 118461 was to check availability of the server and only provide an error if the server has been unavailable for more than a few backups. This was to help support backing up to a work server.

[emilio (emiliomaggio)]

Another strong reason for checking is that preparing uses quite a sizable amount of cpu resources for some time, it is a waste to prepare for a backup if the target is not available.

In my case I use deja-dup on a laptop with the target server available only when I am connected to my home network through wifi. For all the rest of the day travel around and I use a 3G mobile dongle. The connection comes and goes and every time the mobile network becomes available deja-dup prepares for backup, this can happen several times a day.

[Matteo Brancaleoni (mbrancaleoni)]

Hi,

I wish to add my little comment here: maybe is helpful to increase the timeout while waiting for network drives,
which may be "spinned off" to save power.

For example, my synology shuts down the disks when not in use, but if you try to access it, it will power on the disks, but takes at least 20/30 seconds to be 100% available,
Unfortunately dejadup considers this a timeout and no backup is performed.

Maybe can be configurable on a per-target basis?

On my mac, timemachine handles this very well, by just waiting longer.

[Markus Weyermann (byro)]

I got this after upgrading to "mint 18 sarah" (ubuntu 16.04). Adding Nas' IP and Hostname to "hosts" file did resolve for me.

[Markus Weyermann (byro)]

Addition to above post:

May be this relates to events logged on windows members of the same local network:

NetBT 4321: "The name "%2" could not be registered on the interface with IP address %3. The computer with the IP address %4 did not allow the name to be claimed by this computer." (Where "%2" represents the name and Id of the Workgroup, "%3" the name of the event recording client and "%4" the name of the Linux client where scheduled start of dejadup does not work when not having appropriate entry in "hosts" file

bowser 8003: "The master browser has received a server announcement from the computer "%2" that believes that it is the master browser for the domain on transport NetBT_Tcpip_{<Id>}. The master browser is stopping or an election is being forced." (Where "%2" represents the name of the Linux client where scheduled start of dejadup does not work when not having appropriate entry in "hosts" file.)

[Markus Weyermann (byro)]

Sorry, wrong item

Comments #5 & #6 should be moved to #982316. Don't know how.

[Michael Terry (mterry)]

I believe this is fixed in recent 35.x releases (available in Ubuntu artful). Please reopen if you still see this with those versions.