there is a problem when we want to set higher than 8024 (it doesn't allow) , it is supported on linux :, it's supported on linux :
10: tun1@NONE: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 8972 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/gre 10.243.100.21 peer 10.243.100.22 promiscuity 0 allmulti 0 minmtu 68 maxmtu 65511
gre remote 10.243.100.22 local 10.243.100.21 ttl 64 tos inherit numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 tso_max_size 65536 tso_max_segs 65535 gro_max_size 65536 gso_ipv4_max_size 65536 gro_ipv4_max_size 65536