3Com Switch find Uptime

We had another incident with our VoIP phones restarting on Friday. As part of my troubleshooting efforts I needed to be 100% certain that the POE switch providing power to our phone didn't reboot.

To start there is no display uptime command in the CLI. But if you run the display version command part of the output is "Switch 4500 PWR 50-Port uptime is 6 weeks, 5 days, 2 hours, 25 minutes". This is exactly what I was looking for!

It should also be noted that the web interface for the switch shows the uptime on the device summary page.

Mounting a LVM volume in Ubuntu (Live CD)

A while back my testing server crashed. This was no surprise to anyone as it was just a (Very) old workstation. However it was running my nagios install in a production setting. I had been meaning to move it to a proper server, but just hadn't gotten around to it. To make matters worse, I didn't back any of it up. So thankfully it was only the motherboard that failed and not the HDD.

I mounted the HDD in another PC I had sitting around and booted it using Ubuntu Live CD.

First, boot Ubuntu.

Second, install the needed tools:

$ sudo apt-get install lvm2

Third, load the modules to do our task:

$ sudo modprobe dm-mod

Fourth, scan the system for LVM volumes. Look for the volumes you want to mount. Typically this will be VolGroup00:

$ sudo vgscan

Fifth, we need to activate the volume(s):

$ sudo vgtchange -ay VolGroup00

Sixth, Look for the logical volume containing the root file system. Typically this will be LogVol00:

$ sudo lvs

Seventh, create the directory to mount the drive:

$ sudo mkdir /mnt/restore

Eighth, Mount the volume to the directory you just created.

$ sudo mount /dev/VolGroup00/LogVol00 /mnt/restore -o ro,user

Ninth, Copy your files off of the drive.

$ cp /mnt/restore/some/dir/and/path /some/dir/and/path

Tenth, Setup what ever backup means you have on the new server!

All in all this wasn't a terrible thing, it could have been much worse. I have since moved the nagios setup to a virtual machine and am backing it up nightly.

Upgrading the Firmware on a 3com 4500 switch

Again, this is mostly for my own notes, but someone else may find it useful. Last year we purchased a 3c0m POE switch for our new VoIP phone system. This year I needed to update the firmware on it, but with only 8MB of flash drive I ran into a few problems.

First off, BACK UP EVERYTHING!

I used the TFTP method to transfer files to and from the switch. I used Solarwinds TFTP Server on my PC.

File name Prefix / Suffix

s3n / .app = 4500 application software.

s30 / .btm = 4500 boot ROM software

s3p / .web = 4500 web file (HTTP management interface)

3comOScfg.def / .def = 4500 config file

So first things first backing up via TFTP:

<4500>tftp [IP OF TFTP SERVER] put flash:/s3004_01.btm

<4500>tftp [IP OF TFTP SERVER] put flash:/s3p04_03.web

<4500>tftp [IP OF TFTP SERVER] put flash:/s3n03_03_02s56p05.app

<4500>tftp [IP OF TFTP SERVER] put flash:/3comOScfg.def

Please change these files as you see fit. Do a dir on the root directory to get the listing for your particular switch.

Now that we have that backed up we need to clean up the flash:/ drive to make room for the updates.

<4500>delete s3004_01.btm

<4500>delete s3p04_03.web

<4500>detete s3n03_03_02s56p05.app

Now we also have to empty the recycle-bin. This is where I got stuck as I didn't know a CLI could have a recycle-bin, or have never seen it done before.

<4500>reset recycle-bin

See as we now have the free space we need to get the new files we can pull them down from the TFTP server.

<4500>tftp [IP OF TFTP SERVER] get s3p02_01.web

<4500>tftp [IP OF TFTP SERVER] get s3o01_01.btm

<4500>tftp [IP OF TFTP SERVER] get s3n03_02_00s56.app

Again, you will need to use the files that are the current firmware update.

One of the last steps is to tell the switch what files to use on next boot.

<4500>boot boot-loader flash:/s3n03_02_00s56.app

<4500>boot bootrom flash:/s3o02_01.btm

Finally we will save the configuration and reboot the switch.

<4500>save

<4500>reboot

Thats it! After the switch reboots you will be running the newest software, except for the .web file. For some reason this is left out of all of the documentation that comes with the update. I didn't write down the commands I used to get it to update, and I honestly don't think they worked.

Esker Fax 5.0 System Installation

This is mostly just for me. I recently had to build a new server to host our fax software and fax board. I ran into a few problems as I had lost my documentation, so I am posting this link here to remind me should I need to do this in the future.

http://doc.esker.com/edp/5.0/en/installation/index.asp?page=installationa.html

There are some very specific pre-requisets for Windows 2008 that I need to be mindful of in the future, and those can be found at http://doc.esker.com/edp/5.0/en/installation/Content/2008_requirements.html

In reality this was a very simple re-build, that I made more difficult by some rather poor planning on my part.

Locking Down Mozilla Firefox

One of the main draw backs to Mozilla Firefox from most corporate IT people is its inability to be locked down, or taken care of by Group Policy. While you cannot lock down Firefox from within Group Policy alone, you can script these fixes into place to lock settings down.

To start you will need a program to byte shift a config file so that Firefox can read it. I used Byte Shifter.exe. There are also websites that do it all in a browser, but I haven't used them.

You will also need to edit the all.js file in "C:\Program Files\Mozilla Firefox\greprefs\" to include:

pref("general.config.filename", "mozilla.cfg");

I put that line at the absolute bottom, but it might not matter where it goes.

To start create an empty file. I called mine mozilla.txt since the result file will be mozilla.cfg.

The file must start with // on its own line.

Add in any settings you want to lock down. You can peruse about:config for settings, and again after you lock them down to check for the "locked" option.

Below is my mozilla.txt file, with host names changed to protect the innocent. I have included comments (They start with //) to explain things a bit further.

//

//Lock the option for startup page. 0 = "Show a blank page", 1 = "Show my home page", and 3 = " Show my windows and tabs from last time"

lockPref("browser.startup.page", 1);

//Set the home page. Use a pipe to include many home pages as tabs.

lockPref("browser.startup.homepage", "http://www.mysuperawesomecompany.com|https://mail.google.com");

//Set the browser history to something a bit longer than the default 7 days.

lockPref("browser.history_expire_days", 90);

lockPref("browser.history_expire_days.mirror", 90);

// Clean up certain things every time Firefox shuts down. This keeps things clean and running smooth for us, your results may very.

lockPref("privacy.sanitize.sanitizeOnShutdown", true);

//We do not want to clear the history on shutdown.

lockPref("privacy.clearOnShutdown.history", false);

lockPref("privacy.item.history", false);

//We can clean up the downloads history. I have seen things get really slow if this doesn't happen.

lockPref("privacy.item.downloads", true);

//Clear the cache.

lockPref("privacy.item.cache", true);

//Clean up cookies.

lockPref("privacy.item.cookies", true);

//Remove any session info.

lockPref("privacy.item.sessions", true);

//We do not want to keep passwords saved.

lockPref("privacy.item.passwords", true);

//Do not prompt to do this, just do it.

lockPref("privacy.sanitize.promptOnSanitize", false);

lockPref("signon.rememberSignons", true);

//Do not allow the "Show passwords" button.

lockPref("pref.privacy.disable_button.view_passwords", true);

//Don't use a proxy.

lockPref("network.proxy.type", 0);

//We keep one version of Firefox for a while. The newest version breaks things in our application, so we currently need to just run what we have.

lockPref("app.update.enabled", false);

//Disable extensions.

lockPref("config.lockdown.disable_extensions", true);

//Disable themes.

lockPref("config.lockdown.disable_themes", true);

//Show the downloads window when downloading a file.

lockPref("browser.download.manager.showWhenStarting", false);

//Close the downloads window when all downloads are done.

lockPref("browser.download.manager.closeWhenDone", true);

//Save files to:

lockPref("browser.download.useDownloadDir", true);

lockPref("browser.download.dir", "c:\\%homepath%\\Desktop");

lockPref("browser.download.downloadDir", "c:\\%homepath%\\Desktop");

lock{ref("browser.download.folderList", 2);

//Always ask me where to save files.

lockPref("browser.download.useDownloadDir", false);

//Always check to see if Firefox is the default browser.

lockPref("browser.shell.checkDefaultBrowser", false);

//New pages should open in a new window.

lockPref("browser.link.open_external", 2);

lockPref("browser.link.open_newwindow", 2);

//New pages should open in a new tab.

lockPref("browser.link.open_external", 1);

lockPref("browser.link.open_newwindow", 1);

//Warn me when closing multiple tabs.

lockPref("browser.tabs.warnOnClose", false);

//Warn me when openining multiple tabs might slow down Firefox.

lockPref("browser.tabs.warnOnOpen", false);

//Always show the tab bar.

lockPref("browser.tabs.autoHide", false);

//When I open a link in a new tab, switch to it immediately.

lockPref("browser.tabs.loadInBackground", false);

//Block pop-up windows.

lockPref("dom.disable_open_during_load", false);

//Load images automatically. 1 = check 2 = unchecked.

lockPref("permissions.default.image", 2);

//enable JavaScript.

lockPref("javascript.enabled", true);

//Some of the advanced JavaScript options.

//Disable the Advanced Button.

lockPref("pref.advanced.javascript.disable_button.advanced", true);

//Move or resize existing windows.

lockPref("dom.disable_window_move_resize", true);

//Raise or lower windows.

lockPref("dom.disable_windows_flip", false);

//Disable or replace context menus.

lockPref("dom.event.contextmenu.enabled", false);

//Hide the status bar.

lockPref("dom.disable_window_open_feature.status", false);

//Enable Java.

lockPref("security.enable_java", false);

Of course there are others and many more settings, but that covers a good number of them. Also I have only tested this on our version of Firefox, which is 2.0.0.20.

Nagios: check_http, using the --invert-regex option

Some times you want to check that something is running or working correctly and you work out tests for that. Other times you want to know when something is broken and throwing error messages. This is about the latter, a proper HTTP 200 code is great and all, but what if the page is just showing "Too Many Connections" instead of your home page? My old check_http command for this server used to look like, well, check_http. I didn't check anything about it specifically, just that it was returning a 200 code.

Today however I knew I needed something more in depth. Our database server lost its local network connection, but still was available over the public IP, which is what I test against. Once we re-directed the SQL requests to the public IP address of the server everything started working again, until we ran across "Too Many Connections". The database server kept all of the "local" connections open and thus we ate up the rest.

So, how to test for this scenario? After reading through the man pages of check_http I saw this little gem "--invert-regex Return CRITICAL if found, OK if not". This I knew was exactly what I was looking for! If it sees our error codes it will go Critical! Now to put this gem into practice. Here is where the man pages fall short. There is no explanation on HOW to use this, just that it exists. I tried the obvious to me "check_http -H hostname.com -w 3 -c 5 --invert-regex 'Some string'", but that didn't work. OK, lets try "check_http -H hostname.com -w 3 -c 5 --invert-regex='Some string'" nope that errored out with " option `--invert-regex' doesn't allow an argument".

Third times the charm right?

"check_http -H hostname.com -w 3 -c 5 -r 'Some string' --invert-regex '"

# HTTP OK HTTP/1.1 200 OK - 0.355 second response time |time=0.354966s;3.000000;5.000000;0.000000 size=12975B;;;0

Yes, as it turns out third time is the charm. So that got me thinking some more. How can I ensure that the page is rendering correctly, and if it isn't fail but in a specific way?

"check_http -H hostname.com -w 3 -c 5 -r 'Some string I want in my page' -r 'Some string I don't want to see' --invert-regex '"

You can add more than one -r to the check_http command and it will require all of them to be present for the test to pass, and if one of them fails then it will go critical! Perfect!

If you have any more insight into using the check_http command in Nagios I want to hear about it. We are always running into new failure scenarios that we didn't anticipate and I want to know about them before one of my users tells me about it.

Bash: Finding files between two dates in the current directory

Today my boss asked me for a bash command (or script) to find some files between two dates.

Thanks to Jadu Saikia over at Unstableme his post UNIX BASH scripting: Find Files between two dates, I had a starting point.

This will find all files between the two dates (20071019 & 20071121) in this case.

find . -type f -exec ls -l --time-style=full-iso {} \; | awk '{print $6,$NF}' | awk '{gsub(/-/,"",$1);print}' | awk '$1>= 20071019 && $1<= 20071121 {print $2}'

Now, if you want just PGP files you would do:

find *.pgp -type f -exec ls -l --time-style=full-iso {} \; | awk '{print $6,$NF}' | awk '{gsub(/-/,"",$1);print}' | awk '$1>= 20071019 && $1<= 20071121 {print $2}'

The second request that my boss was looking for with this is the file size, something that was being left out by awk. So we can fix that by updating the command to:

find *.pgp -type f -exec ls -lh --time-style=full-iso {} \; | awk '{print $6,$NF,$5}' | awk '{gsub(/-/,"",$1);print}' | awk '$1>= 20090624 && $1<= 20090901 {print $2,$3}'

We added in a $5 to the first awk command, and the final one had $3 added to it. Also I like human readable file sizes so I added -h to the ls command.