vSwitch and DHCP

Similar Questions

• Cisco CallManager and DHCP beyond vswitch

  I have a test lab setup for our managers to call cicso 8.6 running in vmware.  Everythings upward and the work.  However, I can not all phones to pick up my 172.16.1.1 editor/dhcp server IP addresses.  DHCP works very well in the vswitch in vmware, but nothing beyond.  Maybe it's a problem with the configuration on my cisco switch, but I would check here thought incase there is something else I need to do on the vswitch.

  I can ping everything in all directions without problem.  I've got the physical hosts on the cisco switch that can ping the managers of the call and vice versa.  I guess it's a vlan tagging problem, but don't know how to solve this problem.  I do not have a router in the laboratory, only the switch that is configured as the gateway for the managers of the call.

  Call managers - 172.16.1.1 (editor) default gateway is 172.16.1.254
  ... DHCP subnet is 172.16.1.0/24
  .
  VMware vSwitch - no vlan tagging, the vswtich is set to zero (0)
  .
  Cisco 3524 - IP Vlan1 172.16.1.254
  ... The port that connects the switch to host vmware...
  switchport trunk encapsulation dot1q
  switchport access vlan 172
  switchport mode trunk
  switchport voice vlan 172
  spanning tree portfast
  ... The I have a phone plugged into the port...
  switchport trunk encapsulation dot1q
  switchport mode trunk
  switchport voice vlan 172
  .
  .

  Again, I can ping everything in and out of the switch just fine.  I can't get anything on the physical switch to pick up an address 172.16.1.1 dhcp.

  Promisc mode & forging of mac address enabled on your vswitch and portgroup - with out that DHCP does not.

• Requirement of DNS and DHCP Server Essentials 2012 home

  I have a Server Windows Essentials 2012 acting as DNS and DHCP server with a domain name for backups etc on my home network. It's that everything works fine, no errors, no problem. Works well actually, telling me when the children did not install updates or restarted.

  I have two groups of users. My sons step, 10 and 12, which I want to use OpenDNS as a provider external DNS with a policy very, very limited and my wife and me who want to use indications of root or Google DNS or any other DNS provider. Others, specific devices no user (box of the xBox, WII, Satellite, TV, CCTV etc.) can use.

  Before the 2012 server, I had a 2 k 3 server running in a virtual machine for DHCP, alone and put my wife and my devices on static reservations with the just and external DNS provider used OpenDNS as the default scope, DNS. Unfortunately different bits of domain services 2012 don't seem to work unless the server of 2012 is the first DNS server listed on client machines (backups failed. Impossible to find other local computers). Currently, this means that we are all using OpenDNS.

  What I would like is a way to say 2012 to send adult group DNS queries to another DNS provider and leave the rest at default to OpenDNS, while still having them register in the original DNS domain. Any suggestions?

  This issue is beyond the scope of this site and must be placed on Technet or MSDN
  http://social.technet.Microsoft.com/forums/en-us/home

  http://social.msdn.Microsoft.com/forums/en-us/home

• L3 - SG300 - 28 p and DHCP

  Hi all

  I'm having a bit of difficulty up a SG300 - 28 p to L3 and DHCP. I will attach a basic network diagram and a very short list of my needs.

  I'm building a temporary network for a company event 1 day that I can't make it work in our office "Lab".

  L3 - SG300 - 28 p connects to our provider using a connection of the SFP.

  I have to be able to address IP DHCP 300 + using the SG300 - 28 p

  My problem is that I can ping my 2 machines test (manually configured IP) about 172.16.0.3 and 172.16.0.4, but cannot ping after the (internet) referral. Also DHCP distributes no intellectual property for the range 172.16.0.10 - 172.16.1.200

  VLAN 1 is set to 10.2.2.20 access port (to the provider through a connection on port 28 FPS)

  VLAN 100 is 172.16.0.2 access port (ports 1-26)

  I have the WLC and WAP tri...

  Is the set of even possible? I know that the EQ network is a bit budget for users, but for a one day business event I just do not have a budget for the purchase of switches better.

  Please excuse the gross chart.

  Thank you in advance.

  -RJ

  Thanks for the reply.

  With the information that you have provided, it seems the only part missing is the way return the unit for service providers. Unfortunately there is no way around that, and no, you will not be able to put anything between the two, because the device doing the NATting is unity of suppliers.

  I think that what is happening is that traffic is actually the side provider, but there is no way to do so as soon as the provider is not a route for the subnet in 172.16.x.x.

  Out of curiosity, why do you use a VLAN for the devices connected to the SG300? Could you use the 10 subnet Ip addresses? If you do this, you will not need to have a route back from the supplier, as all devices will be on the same subnet.

• function of guard of source IP and dhcp DHCP scope of exhaustion (customer parodies other customers)

  Hello world.

  A dhcp server assigns ip address based on the mac address by equipment of the customer field in the dhcp packets.

  A potential attack is when a crowd of thugs mimics different mac addresses and causes the dhcp server to assign ip addresses until no ip address is left for legitimate host.

  For example, a host with mac1 h1 is designated by the ip address of the dhcp server as:

  199.199.199.1 mac1

  DHCP server has this entry in its database.

  Using hacking tools such as Yersinia or Gobbler can create a DHCP discover messages every time that create another mac for material scope of the client to the dhcp server, thereby causing a dhcp server to assign ip addresses because they are of legitimate dhcp to dhcp server discover messages with matching each another Mac in hardware of client addresses.

  You could use dhcp snooping and it will avoid that (exhaustion of dhcp scope) and configure the switch to check if the CBC mac fits the hardware address of the client in the dhcp message. But when even we can creat spoofed discover messages where mac src in the ethernet header will match the client hardware address in dhcp discovery message. It did not always overcome the problem.

  You might say use IP source guard characteristic but it really will prevent this problem from happening?

  Let me illustrate:

  H1 - f1/1SW - DHCP server

  Let's say that we have configured dhcp snooping on sw1 and f1/1 is untrusted port.  Switch a suite dhcp binding

  199.199.199.1 mac1 vlan1 f1/1

  Then, we configure source ip guard in order to validate the mac src and src ip against the dhcp bindings. When you configure keep source ip first, it will allow dhcp only if a host can request ip address and dhcp binding can be built. After that IP keep source will validate ip or mac src src or both against the binding.depending dhcp on how configure us source ip guard.

  In our case, we have configured source ip guard in order to validate the mac src and src ip against the dhcp binding.

  A dhcp connection is already created as:

  199.199.199.1 mac1 vlan 1 f1/1

  Now, using hacking tools Yersinia or Gobbler on h1, we create our first spoofed dhcp discovery message where mac src = mac2 ethernet header and client harware address = mac2 in dhcp discovery message. As the switch is configured with the function of guard of source ip and therefore allows dhcp discover message to pass through. DHCP server after you receive the message dhcp assigns another IP from the pool. The dhcp server has now after the entries:

  199.199.199.1 mac1

  199.199.199.2 mac2.

  We continue to spoofed dhcp to craft discover messages as described above and are dhcp server keep ip address assignment until exhausts the entire pool.

  So my question is how ip source guard in conjunction with dhcp snooping doesn't stop this attack does not happen? (IE DHCP scope exhaustion)

  I really appreciate your comments.

  Thank you and have a week.

  Hi Sara,.

  Ask was quite interesting. As far as I know that whatever it is port snooping untrusted won't let your fake dhcp server.

  You can take this query in the Sub forum of experts mentioned that is specific for dhcp snooping and source of guard.

  https://supportforums.Cisco.com/message/3689811#3689811

  Please assess whether the information provided is useful.

  By

  Knockaert

• SNMP and DHCP requests on collector

  Hello world

  I want to see the SNMP and DHCP requests on the interface of collector.

  How can I see these queries?

  Y at - it logs through which we can see or some CLI to run on systems CASE.

  Please help me on this and suggest.

  Thank you

  Abuzar

  Hello

  a newspaper would be quickly filled if she provided details on all packages.

  The easiest way is to run a tcpdump on the collector.

  tcpdump for example eth0-i

  You can use tcpdump - help for more info.

  Hope this helps,

  Nicolas

  ===

  Please note the answers that will help you

• Series of unmanaged switches 100 and DHCP

  Hi all, we have a router RV082 switch 8 ethernet ports, it is actually 8 lan with a DHCP address assignment devices (router is used as switch/router and DHCP server).

  Now we need to increase the number of attached LAN devices (other pc, printers, etc.), and we think buy Cisco 100 ethernet switch Series 16 or 24 ports to connect to RV082.

  In this case RV082 will be able to assign DHCP addresses for devices connected to the eth switch ports?

  Thanks in advance.

  Hi Loris, yes it is not a problem. You should be able to switch on a lan port, connect computers to the switch and things should be OK.

  -Tom
  Please mark replied messages useful

• SGE2010 - traffic relay and DHCP configuration

  Hei

  We bought just a switch SGE2010 we want to use to replace the switches in the control panel of our office. So far I managed to access the switch and assigned a static ip.adress on our net, but I can't get to our entry point switch relay traffic. I have a test machine that is configured with a static IP as well and tried the ok sign, but as soon as I put the switch between traffic is not relayed.

  The idea was to use this switch as a DHCP as well. But I thought it would be a start to get at least the traffic relayed before starting the dhcp part.

  Only configuration settings I have done factory settings are the following: (note that the IP is slightly adjusted, but consistent for reasons of confidentiality)

  Configuration of the IP4

  1. Assigned to a static ip address: 95.59.69.148
  2. Assigned a subpattern: 255.255.255.192
  3. Assigned to a user-defined gateway: 95.59.69.129

  DNS configuration

  1. Assigned to an ip address dns address: active 95.59.0.100
  2. Assigned to a dns ip address: 95.59.0.200

  All these settings are the default settings that we use when we assign a server with a static ip address, so it is not a pick up of our filtration dhcp server. So my main question is why on earth isn't it relay traffic?

  In addition, we are interested to kill the former (with stones, I hope) dhcp server and dhcp on the sge2010 configuration. The current dhcp is an operating system. X dhcp server (Yes a mac) with the following configuration:

  • (Dynamic ip) subnet
    From ip: 95.59.69.179
    Ending ip: 95.59.69.190
    Subnet: 255.255.255.192
  • Router ip: 95.59.69.129
    Rental time: 3 hours
  • The range 95.59.69.130 to 95.59.69.149 we set up manually on the servers, hardware, etc.
  • DNS server: 95.59.0.100 & 95.59.0.200
    Default search domain: No. - dns - available.example.com
  • And then we have a group of static mappings to Mac-addresses
    ip address: 95.59.69.150
    IP: 95.59.69.178

  I tried to see in the configuration where I could the mappings static spesify range etc, but I can't say it got me anywhere. So my second question is how to install a server dhcp of Eric as a designated above?

  It's nice to finally convince the CEO to move the dhcp to a better metal, but it's not as nice having a hard time setting up. I would apprecitate every possible leeds and suggestions since I'm kinda stuck.

  Thanks in advance

  Rafn.R

  Hello

  My SGE2000P forwards DHCP requests on my DHCP server.

  I used my default VLAN1 as an interface routed to unicast request DHCP relay on my server (router ISR UC520) that resides on that VLAN 1.

  My interface Vlan 1 on my SGE2000P has an IP 192.168.10.254.

  My gateway address for potential hosts in VLAN 2 IP will be the ADDRESS IP I AI ASSIGNES to VLAN 2, because the PC or the IP hosts connected to VLAN2 will use IP VLAN2 interface as the gateway. It's just how it works!

  Hosts of PC on VLAN 2 need of a default route and they use the IP I assigned to VLAN2 as their next jump out VLAN2 on the real world.

  This address can be seen below.

  

  DHCP relay is enabled with the option 82

  

  I chose VLAN2 as an interface VLAN, as shown below.

  

  I have two ports not signposted in the VLAN2, and I joined an IP host to G1 so that I can test the DHCP relay.

  

  I get the following debug output from my dhcp server, so I know the relay is working.

  002624: 19:40:08.575 Dec 5: DHCPD: looking for expiry of the leases.

  002625: 19:40:58.408 Dec 5: DHCPD: DISCOVER notification to:

  002626: 19:40:58.408 Dec 5: DHCPD: htype 1 CHADRR 0025.84d8.d008

  002627: 19:40:58.408 Dec 5: DHCPD: id remote 020a0000c0a80a0101080001

  002628: 19:40:58.408 Dec 5: DHCPD: id circuit 00000000

  002629: 19:40:58.408 Dec 5: DHCPD: see if there is a specified internal pool class:

  But I must confess that I have opened a case on it with the Small Business Support Center, because I think I can see something wrong on my DHCP server debugging.

  But the key is that I see the router WAN/DHCP server, see the query from DHCP.

  The only way to the broadcast DHCP requests can get to the DHCP server, if the switch SGE2000P takes these DHCP broadcast requests and unicast these or relay to my server DHCP IP address 192.168.10.1.

  So in other words he tries to relay DHCP.

  I would ask you to please check the SGE2010 Administrator's guide because it clearly shows how to configure the DHCP on the SGE2010 relay.

  Even if the screen capture shows and the old version of the code below.  I have day my SGE2000P tonight at the generally available (GA) version of the code.

  

  Just outa interest, if you telnet to the switch, is your mode of layer 3 or Layer 2 switch.

  I can also say from your screenshot that your uplink ports are in overlay mode.

  Maybe if you don't use stacking, you can set your switch to the layer 3 mode and standalone mode

  Best regards, Dave

• VLANS can be configured at the vSwitch and Portgroup level?

  Dear friends,

  I hope that all do you good...

  Two statements are true about groups of ports and VLAN defined on a switch vNetwork Standard? (Choose two)

  A. A VLAN can be configured for the entire virtual switch or on groups of individual ports

  B. several groups of ports can specify the same VLAN

  C. VLAN can only be configured on individual port groups

  D. several VLANS can be specified in a port group

  VLANS can be configured at the vSwitch and Portgroup level?

  B. several groups of ports can specify the same VLAN

  C. VLAN can only be configured on individual port groups

• Why do I need "Promiscuous" Mode when you use multiple vSwitches and a bridge?

  Hello guys,.

  5.5 ESXi running.

  I created two vSwitches and putting multiple virtual machines in each vSwitch. I have a CentOS VM with two network cards, one in each vSwitch. I configured the CentOS VM to work as a bridge. I could spend between devices on a vSwitch pings, but ping has no devices on a vSwitch devices on the other (through the CentOS acting as a bridge). The ARP requests have been sent across the bridge, but have never had sent answers ARP. I checked around online and someone recommended to enable Promiscuous Mode. I activated the Promiscuous Mode (changing to refuse to accept) on the two vSwitches (which is then applied to the change to all virtual machines). You can read more about that here: VMware KB: how "Promiscuous" mode operates on the virtual level switch and portgroup

  Now all of a sudden, everything works.

  My question is: why?

  I think that I don't want to Promiscuous Mode unless it must be such that it will result in more traffic to each VM it had reached before. I don't really understand why I need to authorize this change, and any help would be nice!

  Without promiscuous mode, vSwitch and port group will only transmit traffic VMs (MAC addresses) that are directly related to the port groups, he will not learn the MAC addresses that, in your case, are the other side of the bridge. The "Promiscuous" mode, all traffic is sent to each virtual machine on the vSwitch and port group and it's virtual machine to decide what to do with the network packets. As you have already mentioned, this isn't a parameter that you want to apply to a large number of virtual machines. For this reason, you can create a second group of ports on the vSwitch with only of CentOS virtual machine and activate the "Promiscuous" mode on only this group port rather than the vSwitch.

  André

• Handling VSwitch and network

  Hi, I have have a question: How fact un Working VSwitch , If two virtual machines to communicate between them. If the data on the network is sent to the NIC and then the material or communication is managed in the VSwitch?

  
  

  Greetings from the Germany!

  
  

  Michael Burkhardt

  
  

  If virtual machines are on the same vSwitch and VLAN traffic is not struck the physical network adapter.  If virtual machines have been on different vSwitches, traffic would hit the physical network.  Even if the virtual machines are on different VLAN traffic would pass through your router.

• vSwitch and Portgroup security settings

  I'm looking for a way to query the security settings ("Promiscuous" Mode, forged passes and changes of MAC) the vSwitches and exchanges. MY PS skills are limited. I can get about this until now especially of patching together various scripts that I found. However at this point, I provide a vSwitch and even when I am able to get this information I don't know what to do after that.

  {Foreach ($VMHost in Get-VMHost)

  Foreach ($vSwitch to ($VMHost |)) Get - VirtualSwitch)) {}

  $hostMoRef = get-VMHost $VMhost | % {Get-view $_.} ID}

  $hostNetwork = $hostMoRef.configManager.networkSystem

  $hostNetworkMoRef = get-views $hostNetwork

  $hostNetworkMoRef.NetworkInfo

  }

  }

  PowerCLI 4.1, you can use the property, Extensiondata get to the managed object.

  To display the list of all your vSwitches and their exchanges, security settings, you can do something like this

  foreach ($VMHost in Get-VMHost){
       foreach($vSwitch in $VMHost.ExtensionData.Config.Network.Vswitch){
            Write-Host $vSwitch.Name
            Write-Host "`tPromiscuous mode:" $vSwitch.Spec.Policy.Security.AllowPromiscuous
            Write-Host "`tForged transmits:" $vSwitch.Spec.Policy.Security.ForgedTransmits
            Write-Host "`tMAC Changes:" $vSwitch.Spec.Policy.Security.MacChanges
            foreach($portgroup in ($VMHost.ExtensionData.Config.Network.Portgroup | where {$_.Vswitch -eq $vSwitch.Key})){
                 Write-Host "`n`t" $portgroup.Spec.Name
                 Write-Host "`t`tPromiscuous mode:" $portgroup.Spec.Policy.Security.AllowPromiscuous
                 Write-Host "`t`tForged transmits:" $portgroup.Spec.Policy.Security.ForgedTransmits
                 Write-Host "`t`tMAC Changes:" $portgroup.Spec.Policy.Security.MacChanges
            }
       }
  }
  

  Note that the a security framework for a portgroup will be empty (= not) when he uses the corresponding inherited vSwitch parameter.

  ____________

  Blog: LucD notes

  Twitter: lucd22

• Adding vswitch and portgroup in a stat report information

  Hi - I have a script that details stats for 24 hours. I'm trying to change so that it displays the name of vSwitch the VMNIC is attached to (IE vSwitch0 vSwitch1 etc).  I tried to get the information to display, but I either get a column empty, or I get all vswitches listed in each row.  Any advice?  Thanks in advance

  $date = get-date

  $vccred = import-pscredential-path xxxxxx

  to connect-VIServer-Server xxxxxx-Credential $vccred

  $metrics = "net.received.average", "net.transmitted.average".

  $todayMidnight = get-Date-time-Minute 0 - 0 - 0 second

  $start = $todayMidnight.AddDays(-1). AddSeconds (1)

  $finish = $todayMidnight

  foreach ($cluster Get-cluster | name tri-objet)

  {

  ConvertTo-Html-body"

  $cluster

  " | Out-file - add $htmlNICstats
  
  $clusterTmp = @)
  write-host ">" $cluster
  foreach ($esxImpl in (get-vmhost-location $cluster |)) Sort-Object name))
  {
  write-host ">" $esxImpl

  $ESXHostTMP = @)

  $esx = $esxImpl | Get-View

  {foreach ($vmhost to $esx)

  $stats = get-Stat-entity $esximpl - Stat $metrics - start $start - finishing $finish

  $stats | Group-object - property Instance. where {$_.} {Name - not ""} | %{

  $row = "" | Select Date, NIC, vswitch and NOMCLUSTER, 'Max send Mbps', 'ESX Name","Max has received Mbps. "

  $row.clustername = $cluster.name

  $row.vswitch =

  $row. "" ESX Name ' = $_. Group [0]. @entity.name

  $row. Date = $start. ToShortDateString()

  $row. NIC = $_. Group [0]. Instance

  $row. "" MBps Max Send "=" {0: F2} "f (($_.)) Group | where {$_.} MetricId - eq "net.transmitted.average"} | Measure - Object - property - maximum value). Maximum / 1 KB)

  $row. "" Max received Mbps "=""(($_.) f) Group | where {$_.} MetricId - eq "net.received.average"} | Measure - Object - property - maximum value). Maximum / 1 KB)

  $ESXHostTMP += $row

  $Report = $Report + $row

  }

  }

  $ESXHostTMP | Nic Tri-objet | ConvertTo-Html-property NOMCLUSTER, vswitch, "ESX Name", Date, NIC, "Max send Mbps", "Max received Mbps | Out-file - add $htmlNICStats

  }

  The script looks only at the active network cards.

  $pg = $vmhost.Config.Network.Portgroup |where {$_.ComputedPolicy.NicTeaming.NicOrder.ActiveNic -contains $group.group[0].Instance} | %{$_.Spec.Name}
  

  If you want to include network standby cards as well, this line should be

  $pg = $vmhost.Config.Network.Portgroup |where {$_.ComputedPolicy.NicTeaming.NicOrder.ActiveNic -contains $group.group[0].Instance -or $_.ComputedPolicy.NicTeaming.NicOrder.standbyNic -contains $group.group[0].Instance} | %{$_.Spec.Name}
  

  Let me know if it gives the results you expect.

  ____________

  Blog: LucD notes

  Twitter: lucd22

• vSwitch and NIC.

  Hello

  ESX35, what is the gain in speed if I attribute more than 1 NIC to a vSwitch?  I have a vSwitch with 3 active adapters 100 MB and 1 adapter ensures 100 MB.  This means that the vSwitch can talk to a switch physical gigabit high-speed 300 MB?  I copied a 10 GB from a physical PC to a virtual machine, but do not see a difference between a 3 adapter vswitch and a vSwitch 1 adapter.

  Thank you.

  Exactly.

  Marcelo Soares

  VMWare Certified Professional 310/410

  Technical Support Engineer

  Globant Argentina

  Review the allocation of points for "useful" or "right" answers.

• vSwitch and DvSwitch

  Guys,

  Obviously without revealing review information can someone tell if vSwitches and distributed are covered in one of the reviews that you did for VCP4.

  Anyone know precisely where I can get more information - seem to break the course and labs, but need more information on the switches

  Thank you

  I would say that know the action plan

  http://myLearn.VMware.com/LCMS/mL_faq/2726/VMware%20Certified%20Professional%20on%20vSphere%204%20Blueprint%208.13.09.PDF