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Cisco aci networking for kubernetes confusing me?

How infra vlan 4093 got below ip address, as far as i know that opflex cni ipam plugin managing ip assignment. So where this 10.0.*.* ip come form,  i didnt set such network nowhere in the cluster, either in the apic. Again i have to understand where apic held this ip "DHCPACK from 10.0.*.*", i didnt see any dhcp configuration in the apic.

 

node_subnet: 172.*.*.*/26
pod_subnet: 10.*.*.*/16


ens224.988: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1600
inet 172.*.*.* netmask 255.255.255.192 broadcast 172.*.*.*
inet6 fe80::250:56ff:feac:5387 prefixlen 64 scopeid 0x20<link>
ether 00:50:56:ac:53:87 txqueuelen 1000 (Ethernet)
RX packets 28717 bytes 159758734 (152.3 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 22737 bytes 8157516 (7.7 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

ens224.4093: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1600
inet 10.*.*.* netmask 255.255.0.0 broadcast 10.*.*.*
inet6 fe80::250:56ff:feac:5387 prefixlen 64 scopeid 0x20<link>
ether 00:50:56:ac:53:87 txqueuelen 1000 (Ethernet)
RX packets 58 bytes 3770 (3.6 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 11 bytes 1074 (1.0 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0



Apr 24 00:02:09 sbx43kube01.localdomain network[24835]: [ OK ]
Apr 24 00:02:09 sbx43kube01.localdomain network[24835]: Bringing up interface ens224.4093:
Apr 24 00:02:09 sbx43kube01.localdomain dhclient[25068]: DHCPREQUEST on ens224.4093 to 255.255.255.255 port 67 (xid=0x3f963116)
Apr 24 00:02:09 sbx43kube01.localdomain dhclient[25068]: DHCPACK from 10.*.*.* (xid=0x3f963116)
Apr 24 00:02:11 sbx43kube01.localdomain network[24835]: Determining IP information for ens224.4093... done.
Apr 24 00:02:12 sbx43kube01.localdomain network[24835]: [ OK ]
Apr 24 00:02:12 sbx43kube01.localdomain network[24835]: Bringing up interface ens224.988: Connection successfully activated

 

 

Thanks

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Beginner

Re: Cisco aci networking for kubernetes confusing me?

Finally i got it, it is cluster ip pool which is placed under Tenant infra, apic using this pool to assign ip address to openswitch automatically to establish tunnel interface, there is no configurable dhcp options regarding this, it is factory default setting. Even adding node mac address as an static endpoint, doesnt make sense, apic decide which ip to attach.

View solution in original post

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Collaborator

Re: Cisco aci networking for kubernetes confusing me?

Hi

Is there a yaml file .. something like 

aci-containers-config.yaml

that might shed some light on the subnet you are looking for.

 

#
# Networks used by Kubernetes
#
net_config:
  node_subnet: 10.1.0.1/16      # Subnet to use for nodes
  pod_subnet: 10.2.0.1/16       # Subnet to use for Kubernetes Pods
  extern_dynamic: 10.3.0.1/24   # Subnet to use for dynamic external IPs
  extern_static: 10.4.0.1/24    # Subnet to use for static external IPs
  node_svc_subnet: 10.5.0.1/24  # Subnet to use for service graph--This is not the same as the Kubernetes service-cluster-ip-range: Use different subnets.
  kubeapi_vlan: 4001            # The VLAN used by the physdom for nodes
  service_vlan: 4003            # The VLAN used by LoadBalancer services
  infra_vlan: 4093              # The VLAN used by ACI infra

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/aci/apic/sw/kb/b_Kubernetes_Integration_with_ACI.html 

Highlighted
Beginner

Re: Cisco aci networking for kubernetes confusing me?

No, nothing related,

 

net_config:
node_subnet: 172.*.*.*/26 # Subnet to use for nodes
pod_subnet: 10.*.*.*/16 # Subnet to use for Kubernetes Pods/CloudFoundry containers
# If deployed containers need to access internet, need to have SNAT on this Subnet
# vip_subnet: 10.*.*..*/16 # Subnet to use for virtual IPs (CloudFoundry only)
extern_dynamic: 172.*.*.*27 # Subnet to use for dynamic external IPs ROUTABLE
extern_static: 172.*.*.*/27 # Subnet to use for static external IPs ROUTABLE
node_svc_subnet: 192.1*.*.*/24 # Subnet to use for service graph NOT ROUTABLE
kubeapi_vlan: 988 # The VLAN used by the physdom for nodes (Kubernetes only)
service_vlan: 989 # The VLAN used by LoadBalancer services
infra_vlan: 4093 # The VLAN used by ACI infra

Highlighted
Beginner

Re: Cisco aci networking for kubernetes confusing me?

 

10.*.*.* is belong to apic, its infra management ip in the aci pod, and there is 10.*.*.*/16 network described as a TEP pool for aci pod.

So it seems aci attaching ips from this pool automatically. Waht do you think?

 

Highlighted
Beginner

Re: Cisco aci networking for kubernetes confusing me?

Finally i got it, it is cluster ip pool which is placed under Tenant infra, apic using this pool to assign ip address to openswitch automatically to establish tunnel interface, there is no configurable dhcp options regarding this, it is factory default setting. Even adding node mac address as an static endpoint, doesnt make sense, apic decide which ip to attach.

View solution in original post

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