I have no idea what the best forum is for this so apologies if I have gone to the wrong place!

Here's the situation:

1) Disclaimer: I'm rubbish at this sort of thing so definitely don't assume even remotely know what I'm doing.

2) I have an older Synology NAS, a DS414 running its maximum DSM 7.1.1. This allows a maximum volume size of 16Tb. 

3) There are 4 drives in situ, 2x 18Tb and 2x 8Tb (from back in the days when NAS drives were cheap... 2x18Tb NAS drives form WaterPanther for USD 430!)

4) Setup is currently 2 volumes, vol 1 is almost out of space, and I can't increase the volume size because of the 7.1.1 restrictions. The NAS has about 10 years of backups, photos and music. 

5) I have upgraded the elderly 414 (thanks geek zone!) with a replacement DS420+, running DSM 7.4.1. This should overcome this particular issue and be considerably quicker. Currently it has a couple of spare old 3Tb drives in but no files.

6) I need to move the drives from the old box to the new box, but my understanding is that if I just move them across I am not able to resize the volumes? It appears that the drives need to be set up in SHR on the new box from clean to do this.

Is this correct? I have also seen things on line suggesting shifting one drive at a time allows resizing but seems a high risk situation.... Allegations that if only I understood how the NAS volume thing worked I wouldn't be in this mess are almost certainly correct.

Thanks in advance for your help on this one

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