A question I get asked reasonably often is “Do you know any good free FTP programs?” Yes, I do. It is WinSCP.

Some of the cool features are:

• It does what it is designed to do and does it excellently.
• SFTP, SCP & FTP support (ditch FTP and use SFTP!)
• I’ve never seen it crash.
• Transfer resuming on broken and cancelled downloads.
• Supports SSH keys, so you do not need to remember another password.
• Scripting support; schedule your own remote backups or have sane website rollout procedures!

The WinSCP site describes it as “WinSCP is an open source SFTP client and FTP client for Windows. Its main function is the secure file transfer between a local and a remote computer. Beyond this, WinSCP offers basic file manager functionality. It uses Secure Shell (SSH) and supports, in addition to Secure FTP, also legacy SCP protocol.”

You can download it from here and the obligatory screen shots can be found here.

All of Anchor’s shared hosting plans support SSH & SFTP connections. If you want to read more about how to use SSH, we have some wiki articles that we prepared earlier. These were targeted to cover dedicated & VPS servers however they are still relevant.

• SSH Public Key Authentication
• Securing Remote Access via SSH and Server Security

If you manage an important site, rollout scripts can really make your web site updates pain free. I encourage anyone not using rollout scripts to have a look at the scripting capabilities of WinSCP.

If you follow Australian business news you may have read in the technology news yesterday that auDA has terminated Bottle Domains (Australian Style Pty Ltd) registrar accreditation. This means if you have a domain registered with Bottle Domains or one of its resellers, you will not be able to renew your domain name with that company.

It is possible to transfer .au domain names to another registrar within your registration period free of charge. The remaining period of registration will be carried over to that different registrar. Once your domain name is within 90 days of expiring you will be able to renew your domain name.

If you would like to transfer your domain name to Anchor Systems, you can complete the free domain transfer process online at https://www.anchor.com.au/domain-name-registration/domain-transfer.py, you will need to know your domain name password to complete this process.

If you need to retrieve your domain password, you should ensure you have access to the email address listed on the whois information. You can check your domains records by using our whois tool located here.

If you are unsure on how to complete any of these steps or retrieve your domain name registry key/password please contact our support line on 1300 883 979.

• Ref: http://www.auda.org.au/news-archive/auda-15042009/

Reducing the memory usage in your VPS/VM can be a great way to free up some resources to handle more requests, users or some other metric of win.

By default at Anchor we provision our Red Hat & Cent OS VPS servers with a trim memory usage profile by disabling a lot of unneeded services at install time. We do this by using Trogdor (our hardware/software burninator) and Puppet.

So just what services do we disable, if they exist on the new VPS?

• gpm
• netfs
• pcmcia
• sgi_fam
• yum-updatesd
• pcscd
• rhnsd
• xfs
• hald
• hcid or sdpd
• hpiod or hpssd.py
• dbus-daemon
• cupsd

You can also reap performance gains by changing how you serve content. For example you can use a cut down high performance web server (nginx or lighttpd) to serve all static content, such as images. Then use an Apache process to handle your dynamic requests.

Tuning Apache is deserving of an article all to itself, however some hard and fast rules are:

• Disable all unnecessary modules.

• Work out the per process memory usage, and set your max clients to a suitable number taking into account the available memory and other system daemons.

• Disable htaccess if you do not need it.

PHP is much the same as Apache, disable what you do not need. This goes for any service or application with many optional components.

Knowing the state of your disk IO latency in VMware ESX can help you pre-empt performance & capacity issues before the occur. There are a few guidelines you should keep in mind. These notes are directed towards people using directly attached storage.

• Write latency should be 0, because you have that fancy battery backed controller caching writes, right?
• Read latency should be under 8ms.
• Use the smallest stripe size possible for your RAID array setting. This helps keep random IO performance acceptable at the cost of some sequential performance.
• Do not virtualise very heavy random IO workloads on shared arrays, other guest VMs wont like you for it.
• Unless you have a very compelling reason not too, use RAID 10.

Some other notes, specific to Linux guests are:

• Mount file systems with noatime and nodiratime, this will help reduce random IO.
• Allocate enough memory to have some buffers.
• Do anything possible to stop your VM swapping heavily (see point above).

As with any system, having great monitoring and performance trending allows for you to have an excellent overview of your infrastructure. Even if you don’t have external systems for performance trending, the VMware Infrastructure client with a few tweaks will display the data you want to see.

1. Login to the VI Client.
2. Click on an object in the left navigation tree.
3. Click on the performance tab at the top of the main display pane.
4. Click the “Change Chart Options” button
5. Select the Disk chart option from the left expanding menu.
6. Now change the counters, pick the Latency counters and Number counters, un-ticking the KBps  counters.
7. Save the chart settings as disk-latency.

Now you can view in real time what is happening with your disk IO on the VMware ESX server. If you are more familiar with using a command line and Linux, you can SSH in to the ESX COS and use the command esxtop to view disk performance information.

1. Launch esxtop (as root)
2. Press “v”
3. Press “s” and then “1″

Now you can see the per VM disk usage counters, with a 1 second sample period.

These rules of thumb are also applicable to Xen and Hyper-V.

VMware have just announced that the new version of VMware ESX will be called vSphere.

Some of the announced features are:

• 64bit kernel and console operating system (COS)
• clustered VirtualCenter Servers
• ESX hosts profile management
• cross-hosts virtual networking
• 8-way virtual SMP
• virtual machines fault tolerance across multiple hosts (the famous Continuous Availability presented last year)
• VMs and media library
• alarms on physical hardware faults
• access control on storage resources
• configuration change tracking
• full support for SATA local storage

So it seems VMware are catching up to Xen with some of the features. There will be interesting times ahead in the virtualization space, with the recent release of Citrix XenServer for free.

With an updated kernel and 64bit COS, end users should see more hardware end up on the compatible list which is good news for those who want to use some of the latest and greatest hardware.

Additionally 3rd party vSwitches are going to be supported. Cisco have demoed their Nexus 1000V with vSphere.

What is dstat?  dstat is a versatile replacement for vmstat, iostat and ifstat.

Dstat allows you to view all of your system resources instantly. Eg, You can compare disk usage in combination with interrupts from your HDD controller, or compare the network bandwidth numbers directly with the disk throughput (in the same interval).

No blog post pimping a cool tool would be complete without the obligatory screen shot.

dstat default output

It seems our satire has not been received as such by all and so we have had to remove this post.