How to add ssh public key to Cisco IOS XR devices To enable password-free ssh access to Cisco IOS XR devices, we can import client host's ssh public key to cisco device. Following steps are verified on XRv 9K 6.5.2 device: decode
Unlock root account for VMware ESXi host If the root account get locked out by too many failed login attempts, you lose vsphere web client and ssh access to the host, the only way to unlock is to do it
IPv4 to IPv6 static NAT-PT by Linux box running NAPTD If a client in IPv4-only network, wants to access servers in IPv6-only network, a Linux box can be setup between 2 networks, working as a gateway. It runs NAPTD software, which does IPv4
Neutron L2 Gateway + HP 5930 switch OVSDB integration, for VXLAN bridging and routing Neutron L2 Gateway is a new Openstack project working as a Neutron service plugin. It supports only one use case at the moment, which is to bridge Neutron VxLAN tenant network to physical
Specify floating IP address during creation Starting from Kilo, neutron supports user to specify a floating IP during creation. Before Kilo, neutron allocates floating IP automatically, user has no choice to specify the wanted IP, now this new feature
Neutron ML2 Port Security A new NFV feature, ML2 port security is introduced in Openstack Kilo release. Before this feature, when a neutron port is attached to a VM instance, several anti-spoofing iptables rules are applied to
Metadata service in DHCP namespace How metadata service work by default (in router namespace) In Openstack, by default, you need L3 agent to make metadata service working, which means you need to attach the tenant network to a
Openstack How L3 and DHCP agents HA work in Red Hat OSP7 In Red Hat Openstack Platform 7, l3-agent and dhcp-agents are running in active-active on each controller node, instead of active-standby in OSP6. [[email protected] ~]# pcs status | grep 'l3-agent\|dhcp-agent' -A1 Clone Set: neutron-l3-agent-clone
Cinder NFS backend for Openstack Glance/Cinder/Instance-store In this post, let’s go through how to configure NFS as unified storage backend for Openstack Glance, Cinder and shared instance-store, also we look at how it works under the hood. Setup:
Ditributed Building redundant and distributed L3 network in Juno Before Juno, when we deploy Openstack in production, there always is a painful point about L3 Agent: High availability and performance bottleneck. Now Juno comes with new Neutron features to provide HA L3-agent
meta-data How to use meta-data service for VM with provider network When VM is using provider network, the traffic to network outside cloud passes through physical Router via L2 network, which means in VM, the default route is pointed to physical Router. However, to
How ML2/VXLAN works My setup: 1 controller node + 2 compute nodes RDO Havana 2013.2.2, CentOS 6.5, OpenVSwitch 1.11.0 VXLAN local IPs: controller: 10.142.255.101 compute-1:10.142.255.102
cloud-init How to inject file/meta/ssh key/root password/userdata/config drive to a VM during nova boot There are possibilities to inject something into the VM during nova boot, let’s go through them one by one: The test above is done on Openstack Havana 2012.2.1 @CentOS 6.
diskless Create PXE-Boot image for Openstack Openstack doesn’t support launching a diskless PXE-boot VM, we have to make an image with PXE-boot capability to achieve this. 1.Create a small empty disk file, create dos filesystem. dd if=
availability zone Openstack Zoning - Region/Availability Zone/Host Aggregate Openstack cloud can be zoned from top to down levels, into Regions, Availability Zones and Host Aggregates -Region Each Region has its own full Openstack deployment, including its own API endpoints, networks and
block Openstack VM live migration This post is based assumption that KVM as hypervisor, and Openstack is running in Grizzly on top of RHEL6.4 Openstack VM live migration can have 3 categories: Block live migration without shared
HA Openstack Heat try-out What’s Heat ? Heat is a service to orchestrate multiple composite cloud applications using the AWS CloudFormation template format, it’s Openstack’s implementation of CloudFormation and CloudWatch. Heat integrates other core components
Network Openstack Quantum supported network topologies Quantum support very flexible network topologies, this section we talk about several typical modes. 1. No L3-agent, physical network takes L3 function directly For this kind of network, we only need to create
Grizzly Openstack Quantum LBaaS Openstack Grizzly Quantum Advanced Features Quantum advanced features Environment: Openstack Grizzly running on top of RHEL6.4 1.Namespace Here we try to enable namespace to let quantum to support overlapping IP subnet for tenant networks, also single
Eucalyptus DNS HA Eucalyptus 3 DNS HA configuration tips Eucalyptus 3.0 GA release brings HA features, but it does not use Virtual IP to provide an unique access point to CLC and Walrus service, it uses DNS delegation to privide an
Eucalyptus DNS Setting up external DNS for single frond end Eucalyptus deployment In single frond end setup, Eucalyptus requires a somewhat tricky DNS configuration in order to: have resolvable domain names for internal IP addresses of VMs have resolvable domain names for external IP addresses
