I am using custom-queue to prioritize packets in traffic jam situations according to the IP precedence field (ToS). When there is not fragmentation, the packets are prioritized correctly. When there is fragmentation, however, the IP precedence field is only preserved in the first fragment. Therefore, the other fragments are not prioritized.
How can I solve this? In the case of fragmentation (MTU), the IP precedence field should be the same in all the fragments (packets), should not?