1, you may not have four card, need to use a Vlan switch;
This need your switches support 802.1 Q, the need to dial four switch port (i.e., four ADSL port of the cat) is set to access patterns, vlanID are respectively 10,20,30,40 (of course, other Numbers can also be), connection RouterOS perimeter network port set to trunk mode, and to allow more vlan, in RouterOS wan port to build four vlans, vlanID respectively 10,20,30,40 (corresponding) need to switch on, so as to ensure the multiple cats do not interfere with each other but can and RouterOS virtual vlan interface communication,
/interface vlan
Add the arp=enabled disabled=no interface mtu=1500 name==wan vlan10 vlan - id=10
Add the arp=enabled disabled=no interface mtu=1500 name==wan vlan20 vlan - id=20
Add the arp=enabled disabled=no interface mtu=1500 name==wan vlan30 vlan - id=30
Add the arp=enabled disabled=no interface mtu=1500 name==wan vlan40 vlan id=40 -
2, ADSL unable to dial the number, because used to dial the same MAC;
Vlan if you are attached to the wan port of above, so all vlan interface virtual MAC address is the same, so the telecommunication bureau detected two same MAC trying to dial with two different accounts at the same time will be broken when one of them, which is why others can't dial at the same time,
Solution is by adding a bridge bridge, namely, add images I feel too much trouble, give a script:
/interface bridge,
Add name=bridge10 admin - MAC=11:11:11:11:11:11 disabled=no
Add name=bridge20 admin - MAC=22:22:22:22:22:22 disabled=no
Add name=bridge30 admin - MAC=so when it comes: so when it comes: so when it comes disabled=no
Add name=bridge40 admin - MAC=44:44:44:44:44:44 disabled=no
/interface bridge, port
Add bridge=bridge10 interface=vlan10 disabled=no
Add bridge=bridge20 interface=vlan20 disabled=no
Add bridge=bridge30 interface=vlan30 disabled=no
Add bridge=bridge40 interface=vlan40 disabled=no
So, set the dial, select interface for bridge10 - bridge40, rather than vlan10 - vlan40, this way, dial-up wouldn't exist but unable to dial the MAC address conflict,

It is recommended to use
NETGEAR JFS524E 650
NETGEAR FS726T 999
Huawei S2326TP - SI 1200
Huawei S2326TP EI - 1575
D - the Link DES - 1228-1750
Huawei S2403TP - EA 1785
TP - LINK TL - 1830
SL3428H3C Quidway S2403H EI - 1880
Huawei S2403H - HI 1950
H3C LS - S3100-26 c - SI - AC 2200
H3C LS - S3100-26 c - SI - DC 2200
H3C S3100-26 t - SI (DC) 2400
H3C S3100-26 t - SI - AC 2400
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