To fill the gap between 1G, 10G or 100G ports, Digital Realty also offers aggregated Gigabit Ethernet ports. Link aggregation allows for bundling of up to eight links into one virtual port towards the shared fabric. Link aggregation is also known as EtherChannel, Port Channel, port aggregation (PAgP) or trunking, depending on the vendor involved.

Got a Cisco Catalyst 6xxx? Try this....

interface GigabitEthernet1/1
 description IX Link 1
 no ip address
 no ip redirects
 no ip proxy-arp
 no keepalive
 no cdp enable
 channel-group 1 mode on
!
interface GigabitEthernet2/1
 description IX Link 2
 no ip address
 no ip redirects
 no ip proxy-arp
 no keepalive
 no cdp enable
 channel-group 1 mode on
!
interface Port-channel1
 description IX aggregated link
 ip address 198.32.132.## 255.255.255.0
 no ip redirects
 no ip proxy-arp
 no keepalive
!

Foundry?

!
trunk server ethernet slot/port to slot/port+1
!

Got a Cisco GSR?

!
interface Port-channel1
 description IX Aggregated Link
 ip address 198.32.132.## 255.255.255.0
 no ip redirects
 no ip directed-broadcast
 no ip proxy-arp
 channel-group minimum active 1
 no channel-group bandwidth control-propagation
 hold-queue 150 in
!
interface GigabitEthernet1/1/1
 description IX Link 1
 no keepalive
 no negotiation auto
 channel-group 1
 no cdp enable
!
interface GigabitEthernet1/1/2
 description IX Link 2
 no keepalive
 no negotiation auto
 channel-group 1
 no cdp enable
!

Juniper M-Series can be setup like this...

---
[edit]
admin@junix# show chassis
aggregated-devices {
    ethernet {
        device-count 1;
    }
}
---
[edit]
admin@junix# show interfaces ge-2/1/0
gigether-options {
    802.3ad ae0;
}

[edit]
admin@junix# show interfaces ge-3/1/0
gigether-options {
   802.3ad ae0;
}
---
[edit]
admin@junix# show interfaces ae0
description "IX";
unit 0 {
   family inet {
       filter {
           input IX-in;
           output IX-out;
       }
       address 198.32.132.##/24;
   }
}
---
routing-options {
    autonomous-system ######;
    forwarding-table {
        export [ load-balance ];
    }
}
policy-options {
    policy-statement load-balance {
        then {
            load-balance per-packet;
        }
    }
}
forwarding-options {
    hash-key {
        family inet {
            layer-3;
            layer-4;
        }
    }
}
---