I've two 3G USB modems (or one USB modem and any other network interface - eth or wlan).I connect both interfaces by creating IP rules and adding routes for each one as follows:sb=ip/subnetifn=network interface (ppp0, eth0..etc)ipo=interface ipip route add $sb dev $ifn src $ipo table $tblip route add $sb dev $ifn src $ipoip route add default via $gw table $tbl ip rule add from $ipo table $tblip rule add to $ipo table $tblBoth interfaces get connected and each one connected with its full speed independently. The issue starts when I try to download using both interfaces simultaneously:Open a terminal and start a download on the first interface:curl --interface ppp0 $URL -o /dev/nullOpen another terminal and start a download on the second interface:curl --interface ppp1 $URL -o /dev/null The issue is both interfaces get slower when both commands run together, the first interface starts with 1.5MBps speed, when the next command starts, the first interface starts dropping in speed. The same happens the other way around, when the second interface starts first, speed drops when the first interface starts.It's like auto load balancing occurs. I tried with kernel parameters rp_filter and arp_filter.To be clear, I don't need load balancing, just need each interface run independently for simultaneous connections.Thanks! UPDATEEven with each interface on a different network namespace, they affect each other's speed when run simultaneously.
Multiple network interfaces issue
networking;network interface;modem;mobile