Download Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR).350-501.NewDumps.2021-02-14.31q.vcex

Cisco SD-WAN uses Overlay Management Protocol (OMP) which manages the overlay network. OMP runs between the vSmart controllers and WAN Edge routers (and among vSmarts themselves) where control plane information, such as the routing, policy, and management information, is exchanged over a secure connection.      

Stateful Switchover (SSO) provides protection for network edge devices with dual Route Processors (RPs) that represent a single point of failure in the network design, and where an outage might result in loss of service for customers.  Reference: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SY/configuration/guide/sy_swcg/stateful_switchover.html

Query messages are used to elect the IGMP querier as follows: When IGMPv2 devices start, they each multicast a general query message to the all-systems group address of 224.0.0.1 with their interface address in the source IP address field of the message.  When an IGMPv2 device receives a general query message, the device compares the source IP address in the message with its own interface address. The device with the lowest IP address on the subnet is elected the IGMP querier.  All devices (excluding the querier) start the query timer, which is reset whenever a general query message is received from the IGMP querier. If the query timer expires, it is assumed that the IGMP querier has gone down, and the election process is performed again to elect a new IGMP querier.  Reference: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/15-2_2_e/multicast/configuration_guide/b_mc_1522e_3750x_3560x_cg/b_ipmc_3750x_3560x_chapter_01000.html

The “ip sla 10” will ping the IP 192.168.10.20 every 3 seconds to make sure the connection is still up. We can configure an EEM applet if there is any problem with this IP SLA via the command “event track 10 state down”.  Reference: https://www.theroutingtable.com/ip-sla-and-cisco-eem/

The “mode random one-out of 100” specifies that sampling uses the random mode and only take one sample out of every 100 packets.  

There are two types of hypervisors: type 1 and type 2 hypervisor. In type 1 hypervisor (or native hypervisor), the hypervisor is installed directly on the physical server. Then instances of an operating system (OS) are installed on the hypervisor. Type 1 hypervisor has direct access to the hardware resources. Therefore they are more efficient than hosted architectures. Some examples of type 1 hypervisor are VMware vSphere/ESXi, Oracle VM Server, KVM and Microsoft Hyper-V.  In contrast to type 1 hypervisor, a type 2 hypervisor (or hosted hypervisor) runs on top of an operating system and not the physical hardware directly. A big advantage of Type 2 hypervisors is that management console software is not required. Examples of type 2 hypervisor are VMware Workstation (which can run on Windows, Mac and Linux) or Microsoft Virtual PC (only runs on Windows).  Type 1 is more efficient and well performing, it is also more secure than type 2 because the flaws and vulnerabilities that are endemic to Operating Systems are often absent from Type 1, bare metal hypervisors. Type 1 has better performance, scalability and stability but supported by limited hardware.      

Root guard does not allow the port to become a STP root port, so the port is always STP-designated. If a better BPDU arrives on this port, root guard does not take the BPDU into account and elect a new STP root. Instead, root guard puts the port into the root-inconsistent STP state which is equal to a listening state. No traffic is forwarded across this port.  Below is an example of where to configure Root Guard on the ports. Notice that Root Guard is always configure on designated ports.        To configure Root Guard use this command: Switch(config-if)# spanning-tree guard root  Reference: http://www.cisco.com/c/en/us/support/docs/lan-switching/spanning-tree-protocol/10588-74.html