driverless printing and custom paper size

Hi List,

I have the feeling that I'm in a catch-22 situation. I have a custom 
paper size (being a derivative of the European A4 210x297mm, this one's 
224x297).

Now the printer manufacturer tells me: "define the custom width and 
length of the paper in the print driver software and on the printer 
control panel" - essentially telling me: no, we don't advertise the 
paper sizes you entered on the printer, you'll have to re-define them 
locally.

However, the printer itself is perfectly able to print driverless - or 
at least, that is what I'm thinking when a printer just seems to "add 
itself" through cups-browsed.

This is a Xerox Altalink C8155
cups.lpoptions -p Xerox_AltaLink_C8155_A0_6A_FC -l
... tells me:
PageSize/Media Size: 12x19 3.5x5.5 4x6 5x7 6x9 8x10 A3 *A4 A5 A6 ARCHA 
ARCHB B4 B5 B6 Env10 Env9 EnvC4 EnvC5 EnvC6 EnvDL EnvMonarch EnvPersonal 
Executive FanFoldGermanLegal FolioSP ISOB4 ISOB5 ISOB6 Legal Letter 
Oficio SRA3 Statement Tabloid Custom.WIDTHxHEIGHT
InputSlot/Media Source: *Auto Tray1 Tray2 Tray3 Tray4 Tray5
MediaType/Media Type: *Auto Stationery StationeryPreprinted 
StationeryLetterhead StationeryPrepunched StationeryLightweight 
Transparency Envelope EnvelopePlain EnvelopeWindow Labels Cardstock
cupsPrintQuality/cupsPrintQuality: Draft *Normal High
ColorModel/Output Mode: *RGB Gray
Duplex/Duplex: *None DuplexNoTumble DuplexTumble
OutputBin/OutputBin: *Auto Left Middle Top
StapleLocation/StapleLocation: *None SaddleStitch SinglePortrait 
SingleRevLandscape SingleLandscape SingleRevPortrait EdgeStitchPortrait 
EdgeStitchLandscape EdgeStitchRevPortrait EdgeStitchRevLandscape 
DualPortrait DualLandscape DualRevPortrait DualRevLandscape BindPortrait 
BindLandscape BindRevPortrait BindRevLandscape
FoldType/FoldType: *None Auto Half
PunchMedia/PunchMedia: *None DualPortrait DualLandscape DualRevPortrait 
DualRevLandscape QuadPortrait QuadLandscape QuadRevPortrait QuadRevLandscape
Booklet/Booklet: *False True
cupsFinishingTemplate/cupsFinishingTemplate: *none JogOffset

However, I manually told the printer that Tray 1 now contains 224 x 
297mm paper.

https://www.support.xerox.com/en-us/article/KB0028639 is the Define 
Custom Paper Sizes page from Xerox, that tells to edit the local printer 
driver settings.

I hope someone has an idea how to proceed. Next thing I'll try is to 
actually "add" the printer manually, then change the local paper size in 
the PPD - but that doesn't make me all too happy because it means 
editing it on every computer that needs to print...

Best regards,

Valentijn
-- 
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