MikroTik and SSL website (Comodo)

My old Zyxel (NBG-416N) has no issues connecting to this particular website that uses a Comodo Multi Domain SSL certificate. But after I changed to MikroTik RB750, uploads to the platform were particularly slow, sometimes even failing with the message: Sorry, error occurred on uploading your file. [object ProgressEvent]).

I have no idea what could be the cause..

RouterOS and Firmware 6.43.2

Hi alfred998,

Welcome to the Mikrotik forums. Is the Mikrotik doing the connecting to the website, or are you referring to clients on the LAN side of the Mikrotik connecting to the website on the WAN side?

Yes it is one of the clients in the LAN.

Have you set MTU appropriately and enabled PMTU clamping if necessary?

Hi alfred998,
Could you post your sanitized config? Unless you’re doing mangling on the SSL traffic, I’m not aware of how your Mikrotik could be causing such interference.

I havent done many changes to the default config i think..

(pls let me know if you have any other suggestion after seeing the conf)

# oct/30/2018 09:24:13 by RouterOS 6.43.2
# software id = IXVJ-8FF3
#
# model = 750
# serial number = 467704CDB000
/interface bridge
add name=bridge1
/interface ethernet
set [ find default-name=ether1 ] advertise=10M-half,10M-full \
    auto-negotiation=no speed=10Mbps
set [ find default-name=ether2 ] advertise=\
    10M-half,10M-full,100M-half,100M-full,1000M-half,1000M-full
/interface list
add name=WAN
add name=LAN
/interface wireless security-profiles
set [ find default=yes ] supplicant-identity=MikroTik
/ip pool
add name=dhcp ranges=192.168.42.212-192.168.42.254
/ip dhcp-server
add address-pool=dhcp disabled=no interface=bridge1 lease-time=3d name=dhcp1
/system logging action
add email-start-tls=yes email-to=xXx@gmail.com name=email target=email
/interface bridge port
add bridge=bridge1 interface=ether2
add bridge=bridge1 interface=ether3
add bridge=bridge1 interface=ether4
add bridge=bridge1 interface=ether5
/interface list member
add interface=ether1 list=WAN
add interface=bridge1 list=LAN
/ip address
add address=1xx.1xx.100.94/30 interface=ether1 network=1xx.1xx.100.92
add address=192.168.42.1/24 interface=bridge1 network=192.168.42.0
/ip dhcp-client
add dhcp-options=hostname,clientid interface=ether1
/ip dhcp-server network
add address=192.168.42.0/24 dns-server=8.8.8.8,8.8.4.4 domain=local \
    gateway=192.168.42.1 netmask=24
/ip dns
set allow-remote-requests=yes servers=8.8.8.8,8.8.4.4
/ip firewall nat
add action=masquerade chain=srcnat out-interface=ether1
/ip route
add distance=1 gateway=1xx.1xx.100.93
/ip service
set telnet disabled=yes
set ftp disabled=yes
set www address=192.168.42.0/24 disabled=yes
set ssh disabled=yes
set api disabled=yes
set winbox address=192.168.42.0/24
set api-ssl disabled=yes
/system clock
set time-zone-name=Europe/xXx
/system identity
set name=MikroTik-01
/system logging
add action=email topics=interface
add action=email topics=critical
add topics=critical
add action=email disabled=yes topics=info
add disabled=yes topics=e-mail
/system routerboard settings
set silent-boot=no
/tool e-mail
set address=smtp.gmail.com from=xXx@gmail.com password=xXx port=587 \
    start-tls=yes user=xXx
/tool graphing interface
add allow-address=192.168.42.0/24 interface=ether1 store-on-disk=no
/tool netwatch
add down-script=":log error \"WAN link is down\";" host=8.8.8.8 interval=30s \
    up-script=":log error \"WAN link is up\";\r\
    \n/tool e-mail send to=\"xXx@gmail.com\" subject=\"\$[/system identity \
    get name] WAN link is up \$[/system clock get time]\""