We had to enable SNMP on a XenServer today, I’d never even logged onto one, but it turns out, much like ESX, it’s just a Linux server, at least the good folk at Citrix included nano on there so I didn’t have to struggle with the vi editor!
Solution
First from the web console ensure that SSH access is enabled > Remote Services Configuration > Enable/Disable Remote Shell.
SSH into the host and execute the following commands to start the SNMP daemon, take a backup of the config file, and finally edit the ‘live’ config file.
You can delete EVERYTHING (At the beginning of the file press CTRL+6 to mark the file, then Press ALT+Shif+T (or ALT+T) to cut the text away). Then type in;
[box]
rocommunity {SNMP-String} {IP address or range with /{bits}}
i.e.
rocommunity public 192.168.1.0/24
[/box]
Save and Exit (CTRL+X > ‘Y’ > {Enter}). Now you need to edit the firewall on the host (iptables). To allow the IP addresses of your SNMP collector(s).
[box]
nano /etc/sysconfig/iptables
[/box]
At the bottom, (usually) you will see a deny for ICMP, put an entry for each collector BEFORE that in the following format;
Save and Exit (CTRL+X > ‘Y’ > {Enter}). then restart iptables and the snmp daemon.
[box]
service iptables restart
service snmpd restart
[/box]
If you are polling it though a firewall you can test it locally using this piece of freeware, (I use this to test, but remember to add the local IP you are testing from to the sump config and the iptables!)
Related Articles, References, Credits, or External Links
Last week while trying to create a Linux VM on a VMware ESX 6.5 server, I saw this;
No DEFAULT or UI configuration directive found
Solution
Normally the error indicates theres something wrong with the install media, so I deleted it and uploaded it again, same error. So I downloaded the setup iso file again and checked its checksum, to make sure it was OK, (it was, but the problem persisted).
To fix the problem I simply had to connect to the host, using a different browser, (I used Firefox). Upload the .iso file and start again. Once I did that, hey presto;
Related Articles, References, Credits, or External Links
I’ve had to do a rollout of Remote Desktop Services on Server 2012 R2, and publish it with Active Directory Federation Services and Web Application Proxy. I’m a little rusty on RDS and needed to deploy a few roles, so for my proof of concept I deployed RDS on TWO servers. Below is a run though and my notes on deploying RDS ONLY (I’ll put the links to other articles at the bottom of this post as I write them).
Solution
To save yourself some hassle, visit every server that will be in the Remote Desktop Server deployment, and add all the others into each others ‘server manager’ console.
Manage > Add Roles and Features > Next > Remote Desktop Services Installation > Next.
Standard Deployment. Note: If you choose Quick Start it puts all the roles on one server > Next.
Session-based desktop deployment > Next.
Next.
Select the server that will host the Connection Broker Rule and add it > Next.
Add the server that will host the Remote Desktop Web Access role > Next.
Add the server that will host the Remote Desktop Session Host role > Next.
Tick the ‘restart the destination server automatically if required’ > Deploy.
Finish. (Note: There will be a licensing error, we will address that in a minute).
In Server Manager > Remote Desktop Services > Overview > Note: There are two options yet to be configured, (shown in green). Select ‘RD Gateway’.
Add in the server that will host the RD Gateway role > Next.
Add in the public name of the RD Gateway server, this will generate a self signed certificate, (you can replace this with a proper one later).
Add.
Close
Now Add RD Licensing.
Add in the server that will host the licensing role > Next.
Add
Close
All the nodes should now be displayed..
In production you would now add your Remote Desktop Licences, If you don’t, the whole thing will run for 120 days, (though it continues to nag you about adding licences). I’m content with the 120 day licence for my test deployment. But I will still ‘Activate’ my licensing server.
Follow the instructions
Now you need to create a ‘Collection‘, this is a group of host servers that host applications you can publish. Server Manager > Remote Desktop Services > Collection > Task > Create Session Collection.
Next.
Give the collection a name > Next.
Add in the server(s) running the RD Host role that will be included in this collection > Next.
Select the user groups that you want to grant access to. Here Im simply using the domain users group > Next.
If you want to deploy ‘profile disks’ enter a UNC path to the share > Next.
Create.
Close.
To actually publish applications, select the collection you just created > RemoteApp Programs > Tasks >Publish RemoteApp Programs.
Select the applications, (or add them in if they are not displayed) > Next.
Publish.
Note: You can change certificates from within Server Manger, but I prefer the manual approach, on the RD Gateway Server > Launch the IIS Manager > Select the server > Server Certificates.
Import > Import your publicly signed certificate, (you can use a self signed certificate but DON’T FORGET your remote client needs to be able to check your CRL, and trust your issuing CA if you do).
Sites > Default Web Site > Edit Bindings.
Select ‘https’ > Edit > Add in your certificate > OK > Close.
Bounce the services with an ‘iisreset‘ command.
Update 070316 You also will need to restart the Remote Desktop Services Service!
Connect to the server on the https://{FQDN}/RDWeb address, and you can check the correct certificate is used.
You should now be able to log into Remote Desktop Services Web Access.
Related Articles, References, Credits, or External Links
Seen in Vmware ESX / Vmware Vsphere environments with both ESX and ESXi hosts.
Solution
As far as errors go this one’s pretty straight forward (and very common). I’ve seen it in ESX3 and VSphere networks, with high availability clusters.
It’s complaining because there is only one physical NIC presented to the Service Console (I know ESXi does not have a service console, but it has a management IP).
To fix the problem you can do any one of the following.
1. Ignore the error, HA will still work (though it’s simple to stop it giving an error).
2. Present another physical NIC to the virtual switch that has the Service Console/Management port. On a host with loads of NIC’s that easy, but if your pushed for NIC’s then that’s not an option.
3. The easiest, and my preferred option; You already have Vmotion running for HA, so simply add a Service Console (or a vmkernel management port if your running ESXi) to the vmotion switch, you will never need to connect to it anyway, and it will stop the system presenting this error.
Select your Vmotion switch and select “Add Networking” If you’re on an ESXi host then select “vmkernel”, or on an ESX host select “Service Console”
For ESXi
For ESX
If you are on an ESX host skip to the next step, ESXi users only select use this port for management option. Take note of the IP address of your existing Vmotion kernel port.
Give it an IP address in the same range as your Vmotion ports.
Now you can either wait, or right click each host and select “Reconfigure for HA“
Related Articles, References, Credits, or External Links
Seen in a Virtual Center HA environment – even after selecting “Reconfigure for HA” on the ESX host.
Errors:
cmd addnode failed for the primary node:Internal AAM error – agent could not start – Unknown HA error.
Cannot complete the configuration of the HA agent on the host – See the task details for additional information. Other HA configuration error.
Solution
1. How you proceed depends on your infrastructure. If possible, using vMotion/Migrate all the guest machines on this host, to your other ESX hosts. (Note: if that’s no an option you will need to shut down the guest machines).
2. Put the offending ESX host into maintenance mode (Right click it enter select maintenance mode).
3. Assuming you are connected to the Virtual Center, right click the offending host and select “remove”.
4. Then add it back to the cluster (Right click the cluster and select “Add Host”).
5. HA will be reconfigured on the host as its added back in.
Related Articles, References, Credits, or External Links
I’ve seen this happen a few times now, while looking at your Virtual infrastructure, one or more client machines is greyed out and shown as (Orphaned).
Solution
If you have many guests VM’s on one host with this problem, you can cure this by removing the parent host and re-adding it to the cluster, then right clicking it and select “Reconfigure for HA“.
Or you can do the following, on a machine by machine basis.
1. Right click the affected VM and select “Remove from Inventory” (nothing gets deleted don’t worry.)
2. Select one of your ESX hosts > Configuration > storage > Right click the storage that holds the virtual machine we are dealing with and select “Browse Datastore” > Locate the machines .vmx file > Right click > Add to inventory > Follow the instructions.
Related Articles, References, Credits, or External Links
Error
Task Failed Error: No connections could be made because the target machine actively refused it
Also when trying to connect to VMware VCenter from the Backup and Replication management console;
Error
Failed to connect to “Host-name” by SOAP, port 443, user “User-Name”, proxy srv: port:0
Unable to connect to the remote server No connections could be made because the target machine actively refused it {IP-Address}:443
Solution
There are a few things that might cause this, make sure the Veeam Server can “Ping” the VCenter and the hosts. Also make sure if you use a proxy server there is an exception for traffic going to this IP address.
In my case the problem was simply that the VMware Server service was not running on the Virtual Center.
Related Articles, References, Credits, or External Links
I thought I’d spin up Server 2012 today, and as usual with all new OS’s I run them up in VMware Workstation to take a look (I’m running Workstation 8.0.3 build-703057).
As soon as it started up I was greeted by this.
Your PC needs to restart.
Please hold down the power button.
Error Code: 0x0000005D
Parameters:
0x000000000FEBFBFF
0×0000000020000800
0×0000000000000000
0×0000000000000000
1. In my case it was simply a BIOS setting that needed to be enabled. Enter your system BIOS and locate a feature called Data Execution Prevention, (or No Execute Memory Protection).
2. Enable that setting, then ensure you shut the machine down then manually power it back on again.
Additional Points to Note when installing Server 2012
Make sure on the properties of the VM > Hardware > Processors > Tick Virtualize Intel VT-x/EPT or V/RVI (Note: Virtual support should also be enabled in the host machines BIOS).
VMware Workstation likes to automatically install VMware Tools, Sometimes Server 2012 does not like this and sits with a black screen that will flash blue when you click on it. So to Stop it Installing VMware Tools, Options Tab > VMware Tools > Select Manual. Note: you can always snapshot it and then manually install it later it you want to test. This has been a problem since the early releases of Windows 8.
2. Before you do anything you need to be at ESXi 5.0 U1 for Server 2012 to be supported (That’s build number 623860 or better).
3. However in this case the problem is the same as above, The server in question was an HP Proliant ML 350 G5. Boot the server and press F9 to enter the RBSU > Advanced Options.
4. Processor Options
5. Enable ‘No-Execute Memory Protection” > Exit and save settings.
6. And now we are good to go.
Follow up
04/07/12 Email from Simon Reindl:
I had to update my Bios as InsydeH2O does not offer any tweaking options, It is using Compal Bios (previous 9, now 10 – downloaded from Compal.com. It is using InsydeH20 BIOS on a Compal motherboard. It is a custom build.
Related Articles, References, Credits, or External Links
