nonot1's questions

Is there a command to drop the ZFS and UFS disk caches? (Preferably just one folder hierarchy.)

I'm trying to tuning the performance settings of an application that read/writes data from a large number of files. Mostly read.

In actual use, the app will only run once in a while so the files in question will not likely be cached.

However, since I am testing multiple times in a row, Solaris is trying to be helpful by keeping this files in memory.

Between benchmark runs, can I instruct Solaris to drop anything under /path/to/data from it's caches?

Thank you

I've got a Solaris 10 workstation that I'd like to create a full image backup from. The machine has 2 drives, one UFS for system root, and 1 ZFS for data storage.

I intend to add a third HD to keep the backup images of both primary drives (including any zfs snapshots). The purpose is not disaster recovery, but rather to allow me to easily blow away a series of application installation/configuration changes I intend to try.

What's the best way to do this? I'm not too familiar with Solaris, but have some basic Linux knowledge.

I looked at CloneZilla, but it does not support Solaris. I'm OK with just a dd | gzip > image style solution, but I'd need some way to first zero-out the non-used blocks on the primary drives to aid gzip. They are are much larger than my 3rd drive, but hardly have any real data.

Update to clarify:

1. I specifically want to avoid using any file-system snapshot functionality, because part of the app configuration changes involve/depend slightly on existing and new snapshots. Ideally the full collection of snapshots should be part of the backup.

2. Virtualization not an option, because the goal is to do performance evaluation on a very specific HW configuration. For the same reason, the spurious "back up" snapshots could skew performance data.

Thank you

I have a bunch of folders/files that are 10+ levels deep.

How can I find any symbolic links that point outside this folder tree?

I tried find -type l but this returns all soft links... even those whose destination is with in the folder tree.

Thank you

How can I passively monitor the packet loss on TCP connections to/from my machine?

Basically, I'd like a tool that sits in the background and watches TCP ack/nak/re-transmits to generate a report on which peer IP addresses "seem" to be experiencing heavy loss.

Most questions like this that I find of SF suggest using tools like iperf. But, I need to monitor connections to/from a real application on my machine.

Is this data just sitting there in the Linux TCP stack?

Can I use pfsense or m0n0wall to simulate WAN-like packet loss, jitter, duplication, and reordering?

I see questions looking for dedicated solutions like: What tool(s) can I use to simulate a WAN for HTTP traffic?

But, I'd like to know if it can be done with a regular router distro too. Ideally as a transparent Ethernet bridge, not an actual router.

Thank you

I need to buy a nic that I want to eventually (~3 months) re-use for a VM server deployment that will need to support heavy network I/O. Server is a Xeon Gulftown/Westmere-EP.

Intel has server NICs that support VMDc, VMDq, or both.

Which is the difference?

Which do I want? They both seem to deal with the problem of doing per-VM segmentation at the NIC level, but I don't know which technology better.

See VMDc: http://www.intel.com/network/connectivity/solutions/vmdc.htm

See VMDq: http://blogs.intel.com/idf/2008/08/vmdq_and_vmware_netqueue_will.php?wapkw=(vmdq)

Thank you

How can I set up a tunnel for TCP connections between two hosts so that I can test a few different compression algorithms?

I'm aware of stunnel & SSH, but want to avoid the overhead of encryption. To avoid TCP-in-TCP flow issues, UDP as the transport is fine.

Basically, at the source and destination, I'd like to try piping the TCP data-stream through a few of the widely available compression programs. (gzip, bzip2, lzma, lzo, etc..)

How can this be done? (Using Ubuntu 10.10)

Thank you

I've got a remote server that I can access via SFTP. (Not FTP over SSL. SFTP.)

Periodically, I need to push a few thousand new files to that machine.

How can I:

1. Upload upload these in parallel?
2. Gather statistics, so I can judge the ideal level of parallelization given my particular server/network configuration?

A command line client would be ideal, but a GUI could work as well.

Thank you

How can I configure stunnel to accpet SSL connections, and connect then to an SSL port on a different server?

Here is my setup:

Our ISP's server, "Mail Server", supports smtp/imap over SSL. (Not starttls. Just over ssl.)

But, I have a bunch of client machines that will only trust a specific, internal, root certificate. Thus, they can not connect to "Mail Server".

For these client machines, I'd like to make a dedicated "Mail Tunnel" host that uses stunnel to listen with an in-house signed SSL certificate, and just forward data to "Mail Server" using a 2nd SSL connection.

Can this be done?

What would be the specific steps for Ubuntu Server 10.10? (I'm not too familiar with persistent service configuration.)

Thank you

For coverage reasons, I'd like to deploy 2 wireless access points for my LAN.

Do I just plug both AP's in to the same wired lan, and set them both to the same SSID & PSK? (On different channels, obviously.)

Can I manage a small office of Windows machines with an open source solution? (~15 users)

(XP Pro, but will be moving to Windows 7 Pro as we get new computers over the next few months... as budget and dell vostro sales allow.)

For years, I've muddled though with a default set up of Ubuntu Server + Samba on an old box, and manually configured each client machine to have a shared "S:" drive.

This does work, but it's a huge headache to manually manage each machine. I'd love to be able to lock down the machines and push software installs, updates, and configuration changes from a central location.

I've seen FreeNas but the focus just seems to be on file services and integrating with an existing Windows network.

My specific question is:

What open source solutions exist for managing a SoHo/SMB network of Windows machines and users?

All I need is file service, user authentication, and machine configuration/policy management.

Thank you. :-)