Hello,
I've updated to latest RouterOS 7.1.1 (stable)
When I try link aggregation on my Apple macmini, I receive the message that the switch of MikroTik is not capable of 803.02ad. On the other side an Asus Router there's a simple checkbox to enable: Thanks for any help, I appreciate a lot any effort to make this things work togheter.
Bye.

Which Mikrotik device are you using? Post configuration export (execute /export hide-sensitive file=anynameyouwish from terminal window, fetch file off device, open it with text editor and copy-paste whole contents here inside [code] [/code] environment).

Don't forget to expkain in detail how devices are connected (e.g. which ether ports are used for macmini, ...)

# dec/31/2021 13:40:19 by RouterOS 7.1.1
# software id = 7H8V-J2SH
#
# model = RB2011UiAS
# serial number = E7E30ECED83C
/interface bridge
add admin-mac=2C:C8:1B:FC:75:7A auto-mac=no comment=defconf name=bridge
/interface vlan
add interface=sfp1 name=vlan1 vlan-id=835
/interface pppoe-client
add add-default-route=yes disabled=no interface=vlan1 name=pppoe-out1 \
use-peer-dns=yes user=benvenuto
/interface list
add comment=defconf name=WAN
add comment=defconf name=LAN
/interface wireless security-profiles
set [ find default=yes ] supplicant-identity=MikroTik
/ip pool
add name=dhcp ranges=192.168.88.10-192.168.88.254
/ip dhcp-server
add address-pool=dhcp interface=bridge name=defconf
/port
set 0 name=serial0
/interface bridge port
add bridge=bridge comment=defconf interface=ether2
add bridge=bridge comment=defconf interface=ether3
add bridge=bridge comment=defconf interface=ether4
add bridge=bridge comment=defconf interface=ether5
add bridge=bridge comment=defconf interface=ether6
add bridge=bridge comment=defconf interface=ether7
add bridge=bridge comment=defconf interface=ether8
add bridge=bridge comment=defconf interface=ether9
add bridge=bridge comment=defconf interface=ether10
add bridge=bridge comment=defconf disabled=yes interface=sfp1
add bridge=bridge interface=ether1
/ip neighbor discovery-settings
set discover-interface-list=LAN
/interface list member
add comment=defconf interface=bridge list=LAN
add interface=pppoe-out1 list=WAN
/ip address
add address=192.168.88.1/24 comment=defconf interface=bridge network=\
192.168.88.0
/ip dhcp-client
add comment=defconf disabled=yes interface=sfp1
/ip dhcp-server network
add address=192.168.88.0/24 comment=defconf dns-server=192.168.88.1 gateway=\
192.168.88.1
/ip dns
set allow-remote-requests=yes
/ip dns static
add address=192.168.88.1 comment=defconf name=router.lan
/ip firewall filter
add action=accept chain=input comment=\
"defconf: accept established,related,untracked" connection-state=\
established,related,untracked
add action=drop chain=input comment="defconf: drop invalid" connection-state=\
invalid
add action=accept chain=input comment="defconf: accept ICMP" protocol=icmp
add action=accept chain=input comment=\
"defconf: accept to local loopback (for CAPsMAN)" dst-address=127.0.0.1
add action=drop chain=input comment="defconf: drop all not coming from LAN" \
in-interface-list=!LAN
add action=accept chain=forward comment="defconf: accept in ipsec policy" \
ipsec-policy=in,ipsec
add action=accept chain=forward comment="defconf: accept out ipsec policy" \
ipsec-policy=out,ipsec
add action=fasttrack-connection chain=forward comment="defconf: fasttrack" \
connection-state=established,related hw-offload=yes
add action=accept chain=forward comment=\
"defconf: accept established,related, untracked" connection-state=\
established,related,untracked
add action=drop chain=forward comment="defconf: drop invalid" \
connection-state=invalid
add action=drop chain=forward comment=\
"defconf: drop all from WAN not DSTNATed" connection-nat-state=!dstnat \
connection-state=new in-interface-list=WAN
/ip firewall nat
add action=masquerade chain=srcnat comment="defconf: masquerade" \
ipsec-policy=out,none out-interface-list=WAN
/ip upnp
set allow-disable-external-interface=yes enabled=yes
/ipv6 firewall address-list
add address=::/128 comment="defconf: unspecified address" list=bad_ipv6
add address=::1/128 comment="defconf: lo" list=bad_ipv6
add address=fec0::/10 comment="defconf: site-local" list=bad_ipv6
add address=::ffff:0.0.0.0/96 comment="defconf: ipv4-mapped" list=bad_ipv6
add address=::/96 comment="defconf: ipv4 compat" list=bad_ipv6
add address=100::/64 comment="defconf: discard only " list=bad_ipv6
add address=2001:db8::/32 comment="defconf: documentation" list=bad_ipv6
add address=2001:10::/28 comment="defconf: ORCHID" list=bad_ipv6
add address=3ffe::/16 comment="defconf: 6bone" list=bad_ipv6
/ipv6 firewall filter
add action=accept chain=input comment=\
"defconf: accept established,related,untracked" connection-state=\
established,related,untracked
add action=drop chain=input comment="defconf: drop invalid" connection-state=\
invalid
add action=accept chain=input comment="defconf: accept ICMPv6" protocol=\
icmpv6
add action=accept chain=input comment="defconf: accept UDP traceroute" port=\
33434-33534 protocol=udp
add action=accept chain=input comment=\
"defconf: accept DHCPv6-Client prefix delegation." dst-port=546 protocol=\
udp src-address=fe80::/10
add action=accept chain=input comment="defconf: accept IKE" dst-port=500,4500 \
protocol=udp
add action=accept chain=input comment="defconf: accept ipsec AH" protocol=\
ipsec-ah
add action=accept chain=input comment="defconf: accept ipsec ESP" protocol=\
ipsec-esp
add action=accept chain=input comment=\
"defconf: accept all that matches ipsec policy" ipsec-policy=in,ipsec
add action=drop chain=input comment=\
"defconf: drop everything else not coming from LAN" in-interface-list=\
!LAN
add action=accept chain=forward comment=\
"defconf: accept established,related,untracked" connection-state=\
established,related,untracked
add action=drop chain=forward comment="defconf: drop invalid" \
connection-state=invalid
add action=drop chain=forward comment=\
"defconf: drop packets with bad src ipv6" src-address-list=bad_ipv6
add action=drop chain=forward comment=\
"defconf: drop packets with bad dst ipv6" dst-address-list=bad_ipv6
add action=drop chain=forward comment="defconf: rfc4890 drop hop-limit=1" \
hop-limit=equal:1 protocol=icmpv6
add action=accept chain=forward comment="defconf: accept ICMPv6" protocol=\
icmpv6
add action=accept chain=forward comment="defconf: accept HIP" protocol=139
add action=accept chain=forward comment="defconf: accept IKE" dst-port=\
500,4500 protocol=udp
add action=accept chain=forward comment="defconf: accept ipsec AH" protocol=\
ipsec-ah
add action=accept chain=forward comment="defconf: accept ipsec ESP" protocol=\
ipsec-esp
add action=accept chain=forward comment=\
"defconf: accept all that matches ipsec policy" ipsec-policy=in,ipsec
add action=drop chain=forward comment=\
"defconf: drop everything else not coming from LAN" in-interface-list=\
!LAN
/system clock
set time-zone-name=Europe/Rome
/tool mac-server
set allowed-interface-list=LAN
/tool mac-server mac-winbox
set allowed-interface-list=LAN

I'm using a RB2011UiAS-RM connected to USB 3.1 to Ethernet 1Gb adapter, to Asus is connected the standard ethernet port of Intel macmini (2018)

....you don't have any config on mikrotik for bonded interfaces.

....you don't have any config on mikrotik for bonded interfaces.

I want to aggregate links on macmini not inside the MikroTik router...

Normally bonds (803.2ad) are done for connections between a pair of devices, you seem to mix 3 devices. So if you want to create bond, connect both ethernet cables between mac mini and, say, mikrotik. Or ASUS.
Then configure mikrotik for bonding (read bonding manual) and be prepared for low throughput). Don't expect any kind of high performance though, RB2011 hardware us such that it has internal bottlenecks ...

If you're trying to use ASUS and Mikrotik as separate WAN gateways and to somehow get internet with speed being sum of individual speeds ... then that's something completely different and can only be done with a pretty complicated setup, probably beyond of what's possible to do in mac mini.

I have found a post on Reddit:
https://www.reddit.com/r/mikrotik/comme ... p_for_wan/
But this is what I get (in english for be more helpfull)

I've found this on Youtube:
https://youtu.be/oRu03tdOrak

But I don't know how to create NAT and Mangle rules.
Meanwhile I updated to latest rc version of MikroTik ROuterOS.

Please explain in plain words what exactly would you like to achieve here? It's not clear to me what exactly is your goal and what exactly you are doing to reach that goal. Try to include a chart of intended connections (hand-drawn chart will do, post a photography of it).

Ok.
Now I need help to create firewaal rules for NAT And Mangle for the bonding interface I create.
That's all.

Please explain in plain words what exactly would you like to achieve here? It's not clear to me what exactly is your goal and what exactly you are doing to reach that goal. Try to include a chart of intended connections (hand-drawn chart will do, post a photography of it).

As stated above you can NOT do this. (with bonding)

As stated above you can NOT do this. (with bonding)

With two Asus routers is working, why I can't obtain same results with a MikroTik router in the place of one of the Asus?
(I am running latest Merlin on routers Asus RT-AX88U)

# jan/02/2022 21:41:37 by RouterOS 7.2rc1
# software id = 7H8V-J2SH
#
# model = RB2011UiAS
# serial number = E7E30ECED83C
/interface bridge
add admin-mac=2C:C8:1B:FC:75:7A auto-mac=no comment=defconf name=bridge
/interface vlan
add interface=sfp1 name=vlan1 vlan-id=835
/interface bonding
add lacp-rate=1sec min-links=1 mode=802.3ad name=bonding1 slaves=ether4
/interface pppoe-client
add add-default-route=yes disabled=no interface=vlan1 name=pppoe-out1 \
service-name=wind use-peer-dns=yes user=benvenuto
/interface list
add comment=defconf name=WAN
add comment=defconf name=LAN
/interface wireless security-profiles
set [ find default=yes ] supplicant-identity=MikroTik
/ip pool
add name=dhcp ranges=192.168.88.10-192.168.88.254
/ip dhcp-server
add address-pool=dhcp interface=bridge name=defconf
/port
set 0 name=serial0
/interface bridge port
add bridge=bridge comment=defconf interface=ether2
add bridge=bridge comment=defconf interface=ether3
add bridge=bridge comment=defconf interface=ether6
add bridge=bridge comment=defconf interface=ether7
add bridge=bridge comment=defconf interface=ether8
add bridge=bridge comment=defconf interface=ether9
add bridge=bridge comment=defconf interface=ether10
add bridge=bridge comment=defconf interface=sfp1
add bridge=bridge interface=ether1
add bridge=bridge interface=bonding1 trusted=yes
/ip neighbor discovery-settings
set discover-interface-list=LAN
/interface list member
add comment=defconf interface=bridge list=LAN
add interface=pppoe-out1 list=WAN
/ip address
add address=192.168.88.1/24 comment=defconf interface=bridge network=\
192.168.88.0
/ip dhcp-client
add comment=defconf disabled=yes interface=sfp1
/ip dhcp-server network
add address=192.168.88.0/24 comment=defconf dns-server=192.168.88.1 gateway=\
192.168.88.1
/ip dns
set allow-remote-requests=yes
/ip dns static
add address=192.168.88.1 comment=defconf name=router.lan
/ip firewall filter
add action=accept chain=input comment=\
"defconf: accept established,related,untracked" connection-state=\
established,related,untracked
add action=drop chain=input comment="defconf: drop invalid" connection-state=\
invalid
add action=accept chain=input comment="defconf: accept ICMP" protocol=icmp
add action=accept chain=input comment=\
"defconf: accept to local loopback (for CAPsMAN)" dst-address=127.0.0.1
add action=drop chain=input comment="defconf: drop all not coming from LAN" \
in-interface-list=!LAN
add action=accept chain=forward comment="defconf: accept in ipsec policy" \
ipsec-policy=in,ipsec
add action=accept chain=forward comment="defconf: accept out ipsec policy" \
ipsec-policy=out,ipsec
add action=fasttrack-connection chain=forward comment="defconf: fasttrack" \
connection-state=established,related hw-offload=yes
add action=accept chain=forward comment=\
"defconf: accept established,related, untracked" connection-state=\
established,related,untracked
add action=drop chain=forward comment="defconf: drop invalid" \
connection-state=invalid
add action=drop chain=forward comment=\
"defconf: drop all from WAN not DSTNATed" connection-nat-state=!dstnat \
connection-state=new in-interface-list=WAN
/ip firewall nat
add action=masquerade chain=srcnat comment="defconf: masquerade" \
ipsec-policy=out,none out-interface-list=WAN
/ipv6 firewall address-list
add address=::/128 comment="defconf: unspecified address" list=bad_ipv6
add address=::1/128 comment="defconf: lo" list=bad_ipv6
add address=fec0::/10 comment="defconf: site-local" list=bad_ipv6
add address=::ffff:0.0.0.0/96 comment="defconf: ipv4-mapped" list=bad_ipv6
add address=::/96 comment="defconf: ipv4 compat" list=bad_ipv6
add address=100::/64 comment="defconf: discard only " list=bad_ipv6
add address=2001:db8::/32 comment="defconf: documentation" list=bad_ipv6
add address=2001:10::/28 comment="defconf: ORCHID" list=bad_ipv6
add address=3ffe::/16 comment="defconf: 6bone" list=bad_ipv6
/ipv6 firewall filter
add action=accept chain=input comment=\
"defconf: accept established,related,untracked" connection-state=\
established,related,untracked
add action=drop chain=input comment="defconf: drop invalid" connection-state=\
invalid
add action=accept chain=input comment="defconf: accept ICMPv6" protocol=\
icmpv6
add action=accept chain=input comment="defconf: accept UDP traceroute" port=\
33434-33534 protocol=udp
add action=accept chain=input comment=\
"defconf: accept DHCPv6-Client prefix delegation." dst-port=546 protocol=\
udp src-address=fe80::/10
add action=accept chain=input comment="defconf: accept IKE" dst-port=500,4500 \
protocol=udp
add action=accept chain=input comment="defconf: accept ipsec AH" protocol=\
ipsec-ah
add action=accept chain=input comment="defconf: accept ipsec ESP" protocol=\
ipsec-esp
add action=accept chain=input comment=\
"defconf: accept all that matches ipsec policy" ipsec-policy=in,ipsec
add action=drop chain=input comment=\
"defconf: drop everything else not coming from LAN" in-interface-list=\
!LAN
add action=accept chain=forward comment=\
"defconf: accept established,related,untracked" connection-state=\
established,related,untracked
add action=drop chain=forward comment="defconf: drop invalid" \
connection-state=invalid
add action=drop chain=forward comment=\
"defconf: drop packets with bad src ipv6" src-address-list=bad_ipv6
add action=drop chain=forward comment=\
"defconf: drop packets with bad dst ipv6" dst-address-list=bad_ipv6
add action=drop chain=forward comment="defconf: rfc4890 drop hop-limit=1" \
hop-limit=equal:1 protocol=icmpv6
add action=accept chain=forward comment="defconf: accept ICMPv6" protocol=\
icmpv6
add action=accept chain=forward comment="defconf: accept HIP" protocol=139
add action=accept chain=forward comment="defconf: accept IKE" dst-port=\
500,4500 protocol=udp
add action=accept chain=forward comment="defconf: accept ipsec AH" protocol=\
ipsec-ah
add action=accept chain=forward comment="defconf: accept ipsec ESP" protocol=\
ipsec-esp
add action=accept chain=forward comment=\
"defconf: accept all that matches ipsec policy" ipsec-policy=in,ipsec
add action=drop chain=forward comment=\
"defconf: drop everything else not coming from LAN" in-interface-list=\
!LAN
/system clock
set time-zone-name=Europe/Rome
/system package update
set channel=testing
/system routerboard settings
set boot-delay=9s boot-device=try-ethernet-once-then-nand boot-protocol=dhcp \
cpu-frequency=750MHz force-backup-booter=yes
/tool mac-server
set allowed-interface-list=LAN
/tool mac-server mac-winbox
set allowed-interface-list=LAN

As I wrote with other words in post #7 above, bonding is combining two physical links into a logical link ... between same pair of devices and on L2 (ethernet level). When you try to do it towards two routers, this "bonded" link is not a bond because the other end are two distinct devices in different L2 (ethernet) networks.

In order for bond to work, both devices have to support it on protocol level and that's what you enabled by checking "enable" on Bonding/Link aggregation on ASUS. Which, without further settings, creates "bond" of single physical interface (in other words: useless). As 802.3ad bonding does add some protocol stuff, the other link partner can detect whether a physical link supports bonding or not.

But even if you enable it on both routers (you can do it on Mikrotik, it just takes a bit more than two mouse clicks) it won't really help you. The reason is that with proper bond it doesn't matter which interface packet takes, it'll pass the same IP device next (i.e. same router, firewall, ...). In your case, with bad luck, packets belonging to same connection (to same remote host) might use any of routers alternatively ... as both routers have different WAN IP addresses, those packets will arrive at remote end with different source IP addresses and hence no connection tracking engine (neither server's nor any firewall) would consider them part of same connection.
With some luck (depending on bonding Tx strategy used by macmini) packets of single connection will always use single interface, so the NAT problem described in previous paragraph, won't happen. But what needs to be done is to configure both routers with same IP address space: LAN IP address, same DHCP address range, ... if one uses two routers by same vendor and leaves them at default, then settings will match. Mixing different vendors with different defaults requires manual reconfiguration.
Even if one takes care of IP setup, things can still go wrong if both routers actually serve multi-device LAN. For example: one device requests a DHCP lease from one of routers. Router tries to verify that attempted lease is available and sends out an ARP who has packet. It arrives at your "bonded" device thtough one interface, device replies but with chance of unluck it selects the other interface for response (remember, all bonded links are supposed to terminate inside same L2 network) ... the other router doesn't care about ARP who has reply, the first router doesn't receive reply and assumes IP address is available.
Normaly even simple using each of routers as gateway will likely fail, IP over ethernet assumes that one IP address will be accessible over same MAC address (at least for some time, IP->MAC mappings are cached for some time) ... but in case with two routers (even with same IP address) MAC will be different ... and packets sent to MAC address of router1 via interface connected to router2 will fail to reach its (intermediate) destination.

So once again: what you drawed is not use case for bonding, it's case for multi-WAN and macmini has to do it autonomously (on IP level) while each of ethernet interfaces are considered as separate connections to two different networks (so they have IP addresses from different subnets).