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VCP


Mar
30
comment Network speed between a VM and another machine which is not residing on the same host, is 11MB/s at most
Is your switch smart enough to provide port statistics? Check for errors and flow control.
Mar
21
comment Is it possible to use a single VM image to run many guests (Windows (Server?))?
If you can run it all in Win7, View becomes a no-brainer. VMware web site does a pretty decent job explaining what it is: vmware.com/products/view/overview.html.
Mar
20
comment ESXi Server with 12 physical cores maxed out with only 8 cores assigned in virtual machines
If you have 12 cores and allocate 8 cores total to VMs that run at 100% CPU utilization, the 80% result is about right (allowing for hypervisor overhead). I'm not sure what your objection is. And note that your original issue was with the metric as applied to the host as a whole, which is not discussed in the referenced document, and I can only reiterate that the number you see is pretty much useless. Look at CPU Usage value, like I and ewwhite suggested previously. Hyperthreading is a red herring, you should keep it enabled.
Mar
20
comment VMWare vmfs vs NFS datastore with vmdk?
There's no way to know what will work best without testing with real life loads. Storage system behavior varies widely. I/O profiles vary widely. Don't believe anyone who will tell you "iscsi is faster than nfs" or vice versa.
Mar
20
comment Default gateway is in different subnet. How to configure in RHEL6.2
Sysadmins asking such questions often don't have the freedom to get from their ISP what we tell them would be The Right Thing. I intentionally limited my answer to the options that don't require talking to the ISP.
Mar
14
comment Download file through SSH
If ssh works, you should be able to use scp.
Feb
26
comment DNS split domain architecture while retaining access to split zones
Well, actually you don't have what I described, because you have to juggle your internal servers and the hosted ones. Two suggestions: 1. Forget the true SOA. Set your DNS to own the zone and serve it internally. You'll just have to maintain it in two places. 2. Rely on firewall DNS rewrite. Make it so that during normal operation your clients use internal DNS servers that connect outside through the same firewall that NAT ext.example.com to inside, but during splits the servers that use a different route would kick in. The former will get DNS response rewritten to internal, the latter won't.
Aug
12
comment Redhat ext3 and/or powerpath issue
All you'll get from support is requests to upgrade to current RHEL5 point release and current PP. Considering you're running 5.3 both, those requests won't be completely without merit.
Jul
16
comment CentOS Disks and Mounts
Add output from vgs and lvs please.
Jul
11
comment Virtualisation mini-datacenter setup?
One thing you'll discover once you have the complete vSphere environment up and running is how much other physical stuff you'd love to transition to it. Take care to build it properly right from the start, you won't regret it.
Jul
11
comment Troubleshooting firewall and routing on Linux
See if your version of iptables supports TRACE target.
Jul
11
comment Virtualisation mini-datacenter setup?
That means you'll never get any support from VMware. Every time your ESXi host PSODs, you won't be able to do anything other than reboot and hope it doesn't happen often. And think again about the no-64-bit-guest issue. Can you guarantee all your current and future guests will be 32-bit? I strongly believe that at this point your best move would be asking another question on Serverfault, something like "what's the cheapest reliable hardware platform for ESXi 4.1?" I wish I could help here, but we're a single vendor (Dell) shop, and I don't know much about white box alternatives.
Jul
10
comment Virtualisation mini-datacenter setup?
Yup. You're out of luck. You won't be able to run 64-bit VMs, they're not on ESX(i) 4 HCL, and in general those CPUs are just not good enough. This doesn't mean you can't make things work with that hardware, it's just seems somewhat pointless: you'll sink a lot of effort into something that will never give you good results and will never be supported by VMware.
Jul
9
comment Virtualisation mini-datacenter setup?
Please specify the generations of your Proliants. Based on the CPU specs, I strongly suspect they're too old to run ESXi properly. And based on your other comment I'm pretty certain you'll need at least two new switches. And you should also specify what NICs you have in these servers. Don't expect to get away with just the built-in pair of ports.
Jun
27
comment Is this a solid (and cheap) High Availability idea for my website and database if the zombi's attack?
Yes. You're thinking about registrars and their records. Those do take time, because their databases may not be updated immediately, and then the TTLs of those records are usually set very high. But when you have a DNS server that you can reload immediately and a low TTL, those issues don't exist. Moreover, DNS is the foundation of all load balancing solutions that provide multi-site capabilities (google "GSLB").
Jun
24
comment Is this a solid (and cheap) High Availability idea for my website and database if the zombi's attack?
Find a reliable DNS provider that allows low TTL, set the TTL for the web site to 300sec or so, and you won't need to worry about propagation delays. All properly configured DNS servers will follow TTL, and most (if not all) web browsers expire their DNS cache after 15 minutes. So the worst case delay will be 20 minutes, well within your downtime window.
Jun
20
comment ESX shut down VMs when some but not all storage paths failed
This looks very much like HA isolation response. Though that's not supposed to react to storage changes. However, if your hosts didn't handle path loss gracefully and froze for any extended period of time (15 sec or more), they could get the impression that they couldn't communicate to each other and trigger isolation response.
Jun
10
comment Is an Apache use TCP port on each connection?
Not URL. "man socket".
Jun
8
comment Design Critique Needed ( VLAN & ESXi )
Separate FT to its own pNICs and VLAN. Combine vMotion and management in the same vSwitch with two pNICs, assigning the two vmknics to different pNICs. This way the only case when vMotion and management will share a network path is if one of those two pNICs fails. And your DATA is not just DMZ. It's everything - including management VLAN for VMs (don't put VM traffic where your management vmknic is). So, the two DATA pNICs should be trunks, not access ports.
May
27
comment Going from Ubuntu to CentOS
Stay away from CentOS until its dev team has figured out its politics.