MacVTap

How to create a MacVTap.

Boundary conditions:

• libvirt will automatically create a MacVTap interface when you configure a direct connection.
• lsmod | grep macvtap
• lsmod | grep bonding

[root@kvm1awb images]# lsmod | grep macvtap
macvtap                22693  1 vhost_net
macvlan                19150  1 macvtap

[root@kvm1awb images]# lsmod | grep bonding
[root@kvm1awb images]# modprobe bonding
[root@kvm1awb images]# lsmod | grep bonding
bonding               160781  0

Step-by-step process:

1. Create a network interface

1.1 To find a interface name of a qeth device lsqeth -p

1.2 znetconf -u

1.3 znetconf -c

1.4

# ip addr add <IP-address> dev <network-interface-name>
# ip link set <network-interface-name> up

1.5

ip link set <network-interface-name> qlen 2500

1. Create a bond interface for high availability

1.1 Add a new bonded interface dinamically 1.2 Verify the existing bond interfaces

[root@kvm1awb /]# cat /sys/class/net/bonding_masters
bond0

1.3 Let's create the bond5

[root@kvm1awb /]# echo "+bond5" > /sys/class/net/bonding_masters
[root@kvm1awb /]# cat /sys/class/net/bonding_masters
bond0 bond5
[root@kvm1awb /]# ip link show bond5
22: bond5: <BROADCAST,MULTICAST,MASTER> mtu 1500 qdisc noop state DOWN mode DEFAULT
    link/ether 86:91:ae:e0:8a:98 brd ff:ff:ff:ff:ff:ff
[root@kvm1awb /]#

1.4 Specify some bonding parameters

Questions: what is the default? balance-rr ?

[root@kvm1awb /]# echo "active-backup 1" > /sys/class/net/bond5/bonding/mode
[root@kvm1awb /]# echo "100" > /sys/class/net/bond5/bonding/miimon
[root@kvm1awb /]# echo "active 1" > /sys/class/net/bond5/bonding/fail_over_mac
[root@kvm1awb /]# cd /sys/class/net/bond5/bonding/
[root@kvm1awb bonding]# ls
active_slave   ad_partner_key     arp_interval   fail_over_mac  min_links     primary           slaves
ad_actor_key   ad_partner_mac     arp_ip_target  lacp_rate      mode          primary_reselect  updelay
ad_aggregator  ad_select          arp_validate   miimon         num_grat_arp  queue_id          use_carrier
ad_num_ports   all_slaves_active  downdelay      mii_status     num_unsol_na  resend_igmp       xmit_hash_policy
[root@kvm1awb bonding]# cat fail_over_mac
active 1
[root@kvm1awb bonding]# cat miimon
100
[root@kvm1awb bonding]# cat mode
active-backup 1

1.5 Add the network interfaces on the KVM Host

[root@kvm1awb bonding]# znetconf -a 4100 -o layer2=1
Scanning for network devices...
Successfully configured device 0.0.4100 (enccw0.0.4100)
[root@kvm1awb bonding]# znetconf -a 4103 -o layer2=1
Scanning for network devices...
Successfully configured device 0.0.4103 (enccw0.0.4103)
[root@kvm1awb bonding]# znetconf -a 5703 -o layer2=1
Scanning for network devices...
Successfully configured device 0.0.5703 (enccw0.0.5703)
[root@kvm1awb bonding]# znetconf -c
Device IDs                 Type    Card Type      CHPID Drv. Name             State
--------------------------------------------------------------------------------
0.0.4100,0.0.4101,0.0.4102 1731/01 OSD_1000          01 qeth enccw0.0.4100    online
0.0.4103,0.0.4104,0.0.4105 1731/01 OSD_1000          01 qeth enccw0.0.4103    online
0.0.5703,0.0.5704,0.0.5705 1731/01 OSD_1000          0C qeth enccw0.0.5703    online
0.0.570a,0.0.570b,0.0.570c 1731/01 OSD_1000          0C qeth enccw0.0.570a    online

1.6 Add slaves interfaces

If you try to execute this command without follow the steps 1.x, you will receive an error:

# ip link set enccw0.0.4100 master bond5
RTNETLINK answers: Operation not permitted

1. Optional: Create a virtual LAN (VLAN) interface.