vSphare Distributed switch or vDS
vSphare Distributed switch or vDS:-vDS Spans multiple ESXI hosts in a cluster instead of each hosts having its own set of vSwitches...... Provides a centralized “network controlling mechanism” across all the ESXi hosts.........And reduces network complexity in clustered ESXi environments....... simplifies the addition of new hosts to an ESXi cluster environment with guaranteed consistency of network configuration across the cluster.
Features:-
(i) Inbound traffic shaping
(ii) VM’s network port block
(iii) Private VLANs
(iv) Load-based teaming system
(v) Datacenter-level network management
(vi) Network vMotion
(vii) vSphere
switch APIs
(viii) Per-port policy
settings
(ix) Individual Port’s state
monitoring
(x) Link Layer
Discovery Protocol (LLDP)
(xi) User-defined traffic paths for
QOS
(xii)
Monitoring NetFlow
(xiii)
Port Mirroring
■ Inbound traffic shaping:- This port group
setting that can throttle or control the aggregate bandwidth inbound to the
switch. vSS has outbound traffic shaping only while vDS has both.
■ VM’s network port block:- We can block a Specific switch
ports for a specified VMs use.
■ Private VLANs:- In essence, a PVLAN is a VLAN
within a VLAN. PVLANs in your vSphere environment can be kept from seeing each
other.
■ Load-based teaming:-
This teaming system evaluate current load on each link and make frame
forwarding decisions to balance load.
■ Datacenter-level network management:- A vDS is
managed from the vCenter server as a single switch. This provides a centralized
network control mechanism and guarantees consistency of network configuration
across the entire ESXI host connected.
■ Network
vMotion:- Because a port group that is on a vDS is actually
connected to multiple hosts. While vMotion a VM can migrate from one host to
another without changing ports and port group settings such as security,
traffic shaping, and NIC teaming etc.
■
vSphere
switch APIs:-Through this
APIs third-party distributed switches such as the Cisco Nexus 1000v can
be used as a, virtual appliance (VA).
■ Per-port policy
settings:- Most of the configuration on a vDS is at the port group
level, but it can be overridden at the individual port level giving tremendous
flexibility.
■ Individual Port’s state monitoring:- Each
port on vDS can be managed and monitored independently of all other ports
helping quickly identify port issues.
■ Link Layer
Discovery Protocol:- Similar to Cisco's, Cisco Discovery Protocol
(CDP),Link Layer Discovery Protocol (LLDP) enables vDSs to discover other
devices such as switches and routers that are directly connected (linked) to
them.
■ User-defined traffic paths for QOS:- You can
set up a quality of service (QoS) (of a sort), by defining the traffic paths by
types of VMware traffic. In earlier versions of vDSs, you could define traffic
as vMotion, Management, storage and others, but now you can define your own
categories.
■ Monitoring NetFlow:- This enables you to easily
monitor virtual network flows with the same tools that you use to monitor
traffic flows in the physical network. Your vDS can forward virtual NetFlow
information to a monitoring machine in your external network.
■ Port Mirroring:- Port mirroring sends a copy
of -"packets to be sent"- to a monitoring station so that traffic
flows can be monitored without the IPS/IDS (intrusion prevention and detection
system)skewing the data.
dvUplink
groups:-Each
host keeps its own network configuration in a hidden switch that is created
when you add a host to a vDS. dvUplink groups connect those hidden switches
that are contained in your hosts to vDS and then from there to the physical
world.
PVLAN
or Private VLAN:-In essence, a PVLAN is a VLAN within a
VLAN. The PVLANs in your vSphere network can be kept from seeing each other. In other words by using PVLANs,
you can isolate hosts from seeing each other while keeping them on the same IP
subnet
PVLANs are configured in pairs: the primary VLAN
and any secondary VLANs. The primary VLAN is considered the downstream VLAN;
that is, traffic to the host travels along the primary VLAN. The secondary VLAN
is considered the upstream VLAN; that is, traffic from the host travels
along the secondary VLAN. There are 3 types of PVLANS:-
1. Community: This
a private VLAN used to create a separate network to be shared by more than one
VM in the primary VLAN. VM's on community VLANs can communicate only to other
VMs on the same community or to VMs on a promiscuous VLAN.
2. Isolated:
This is a
private VLAN used to create a separate network for one VM in your primary VLAN.
It can be used to isolate a highly sensitive VM. If a VM is in an isolated
VLAN, it will not communicate with any other VMs in other isolated VLANs or in
other community VLANs. It can communicate only with promiscuous VLANs.
3. Promiscuous: VMs
on this VLAN are reachable and can be reached by any VM in the same primary
VLAN. In PVLAN parlance, a promiscuous port is allowed to send and receive
Layer 2 frames to any other port in the VLAN. This type of port is typically
reserved for the default gateway for an IP subnet — for example, a Layer 3
router.
Cisco Discovery Protocol (CDP):- a Cisco protocol
for exchanging information between network devices.
Link Layer Discovery Protocol
(LLDP):- An industry standardized form of CDP. Through LLDP, ESXi hosts
participating in a dvSwitch can exchange discovery information to physical
switches. Discovery information includes information on the physical NIC use
and the vSwitch involved.
vDS
versions available-4.0 ,4.1, 5.0,
5.1, 5.5, 6.0
vSphare license for dvSwitch- Enterprise
Plus
Can a ESXi host use vSS and vDS
together- Yes.. you can use vSS and
vDS together. Even you can leave your VMkernel ports in standard switch while keeping
your entire VMport groups on Distributed switch
Difference
between vSS and vDS Trafic shaping-
With vSphere Standard Switches, you could apply
traffic-shaping policies only to egress (outbound) traffic but with a Distributed
switch, you can apply traffic-shaping policies to both ingress (inbound) and
egress traffic.
Difference
between vSS and vDS Load Balancing-
version 4.1 and version 5.0 vDS support a new
load balancing type,
Route
Based On Physical NIC Load. When this load-balancing policy is selected, ESXi checks the
utilization of the uplinks every 30 seconds for congestion. In this case,
congestion is defined as either transmit or receive traffic greater than 75
percent mean utilization over a 30-second period. If congestion is detected on
an uplink, ESXi will dynamically reassign the VM to a different uplink.
vDS Total Ports and Available ports-
With vSphere
Standard Switches, the VMkernel reserved eight ports (8) for its own use,
creating a discrepancy between the total numbers of ports listed in different
places.
For every
host added to a Distributed switch (vDS), four ports (4) by default are added
to the “vDS Uplinks” port group which are reserved for uplinks. So, a vDS with
three hosts would have 140 total ports with 128 available, a vDS with four
hosts would have 144 total ports with 128 available, and so forth.
vDS
Distributed
Switch
vSS Standard switch
2 Hosts =128+(4X2)=136 Maximum Port per vSwitch 4096
3 Hosts=128+(4X3)=140 Maximum Port per Host 4096-8
4 Hosts=128+(4X4)=144 =4088
nice post
ReplyDelete