Dear experienced bird experts! :) While trying to setup my first more complex bird config I cannot determine the error I made that impede my config from working. Excerpt from the config: table kern_wimz; function is_wimz_self_nets() { return (net ~ [10.56.0.0/16+, 10.37.0.0/16+]); } # import only self from kernel, export anything but wi&mz - remark: exporting done by other kernel protocoll instances protocol kernel kern_import { scan time 30; import where is_wimz_self_nets(); export none; table kern_wimz; kernel table 254; # main }; I also added a - seemingly neccessary: table bla; protocol device { scan time 30; table bla; }; (Complete config: https://github.com/freifunk-mwu/technik-meta/wiki/birdconfig ) In the main kernel routing table (#254) one can find - among others - the two prefixes 10.37.0.0/18 and 10.56.0.0/18 . I expected these two to be imported into kern_wimz. From there they are going to be transported to other tables by the pipe protocol. But kern_wimz remains empty. :( I consulted the documentation multiple times already, but I cannot pinpoint the mistake I made. Could anyone please provide me with a helpful hint? Best regards, Kai