Our Cacti installation was not showing our complete “data source” title length under the “Graph Management” menu. But instead trimmed the title with three dots at the end (…) . Which made it impossible to select the right datasource to use.
This is not a value you can change in the GUI. If you want to change this you need to dive into the PHP code instead. Let’s just do that.
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Do you hate it too? When you are going through some DHCP logfiles/leases you see those:
[18:53][martin@cerberus:~]$ leasecheck.pl |grep -i .34
10.0.0.34 2014/01/24 11:41:36 2014/01/25 11:41:36 04:46:65:75:4f:65 active android-66627f1e652e4864
For some time now i wanted to change my mobile phone “hostname”. Android uses a couple of different hostnames though. You have /etc/hosts, bluetooth hostname (which you can change with GUI), network hostname, etc. I wanted to alter the network/WiFi hostname. So my device gets a proper DDNS entry which i can remember;). And now the number of Android devices are growing in my household I can better keep up with who-is-who in logfiles/etc.
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Gloeiende Oliebollen. I wanted to DHCP relay discovers MSGs off only ‘one’ specific device in my home network somewhere to the DHCP server on the other side of a GRE tunnel. Off course this is not really logical but that’s besides this post.
I installed ISC DHCP “yum install dhcp-4.1.1″. This packages comes with the ISC dhcrelay client which I figured to do the relaying. The Idea was to block all broadcast traffic designed for port 67 on this machine, and only to allow the specific MAC address.
When this was setup, I noticed all the local DHCP discovers/MAC’s passing the filter and thought I made a mistake. I did some troubleshooting and started with blocking individual MAC’s. This is normally an easy task by doing:”-A INPUT -m mac –mac-source 00:02:02:41:d0:77 -j DROP” and checking the hit counter of IPtables.
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I while ago I installed PowerTop on my server. PowerTop (Intel) is an awesome utility if you’re looking into the power consumption of you computer. It’s even cooler (literately) if you use it on a laptop because i says how much power you’re drawing from the battery in watt/hour and gives you ton’s of information what is causing that battery drain you’re experiencing. I used it on my server and back then in didn’t noticed it, but after updating it an hour ago to the latest release it caught my eye that the USB devices/Controller is consuming 100% of the power usage:
Not something really important because the USB power capacity is pretty limited anyway:
[21:41][martin@kvm:~]$ sudo lsusb -v|grep -i maxpower
MaxPower 0mA
MaxPower 0mA
MaxPower 0mA
MaxPower 0mA
MaxPower 100mA
MaxPower 100mA
But probably “irritating” at best for a guy in IT. How to fix this?
We moved our Nagios installation to a new (High performance) server. Some users started complaining that with every refresh of their browser screen the http password box appeared and asked for the login and password of the secure site.
After some searching around in log files it hit me:
10.248.2.198 – blaat [05/Dec/2012:16:00:13 +0100] “GET /nagios/media/hostdown.wav HTTP/1.1” 401 493 “-” “NSPlayer/12.00.7601.17514 WMFSDK/12.00.7601.17514”
10.248.2.198 – blaat [05/Dec/2012:16:00:15 +0100] “GET /nagios/media/hostdown.wav HTTP/1.1” 401 493 “-” “NSPlayer/12.00.7601.17514 WMFSDK/12.00.7601.17514”
The browser (IE 9.x in this case) loads the “status.cgi”. Because there is a hostdown, I wants to play the according media file. IE apparently don’t has any build in decoder for .wav files. And it uses the NSplayer embedded within IE for this. Problem is that somewhere between parsing and remembering the L&P for this site/file there goes something wrong. Because with every refresh (and thus every get of the .wav file) the password box pop-ups.
Highly annoying. Not want to lose to much time to fix this, I decided that the easiest way was to make all *.wav free files.
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So you’re on the road. Being the road warrior you are, you can appreciate the finer things in live. For example some privacy while surfing the web (never heard of that anyway, but lets continue). Be it in a boring hotel room, a local coffee bar, or some other place connected through the Internet by means of WiFi. Using an WiFi encryption will probably make your browsing session a private one from “strangers” who are trying to eavesdrop on you, but if the know the pre-shared-key (WEP/WPA) the can still with a little bit of trouble read your data/information! And none the less, the proprietor of the gateway/router is often still in the position to eavesdrop on all the websites (and content) of websites you’re visiting.
Even if you’re visiting an SSL website they still can see “which” website you’re visiting. From there on everything is encrypted (including the URL’s, payload, etc).
There’s this magnificent little 444KB program called putty.exe . Mostly you use it to connect from a Windows PC to a (distanced) server running an SSH daemon to manage the hosts. Nobody can eavesdrop on you because it’s completely encrypted. Butt this program has some really nice/crazy features. It can act as you local (HTTP) socks proxyserver when you’re on the road.
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Today I had the pleasure to change 150 of our 200 DHCP pools. We had to extend it with an extra option (yea, this was quicker to make the changes by hand instead of writing/figuring out a way to do it by scripting) . When I was done I wanted to ‘quickly’ check my work for (human) errors and came up with the following “quick” check:
#
#$ FTTH XXX customers XXXX
#
subnet 77.x.x.128 netmask 255.255.255.128 {
option subnet-mask 255.255.255.128;
option broadcast-address 77.x.x.255;
option routers 77.x.x.129;
option domain-name "xxxxxxxxx.xx";
option domain-name-servers x.x.x.x, x.x.x.x;
option 6rd 17 41 0x2a02 0x80c0 0xfe00 0 0 0 0 0 x.x.x.2;
pool {
allow members of "max-lease-per-service";
max-lease-time 1810;
default-lease-time 1810;
deny dynamic bootp clients;
range 77.x.x.130 77.x.x.254;
}
}
The 6rd line is the one we added. I wanted to check if specific (networkid/17) pools we all had an 6rd line:
Normally I use grep, so i glanced at the man page and came up with:
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I was trying to setup (SSH) Internet access to github.com on some servers wich don’t have any Internet connectivity.
I wanted to use SSH instead of HTTP because this way you can use encryption keys instead of username and password authentication for github.
There are some excellent guides out there how to do this with corkscrew. I used one of those and almost got it working …… :
[martin@dhcp3b.hgl-pv ~]$ corkscrew 10.255.248.131 8080 github.com 22
Proxy could not open connnection to github.com: Forbidden
putty displayed the same error so the problem was probably with the proxy. If you need to fix this allow the (Squid) proxy to be able to open a connection to port 22.
I recently received the new keyboard I bought for my “Small closet home server” project. I opted for a “compact” keyboard but with normal sized keys on it. So the manufacture had to remove some keys.
This resulted in removing among others the numeric keypad. Unless you work in accounting/administration you probably don’t use those keys often. And the times that you dot need them you can use the ‘normal’ numbers part or use the function (Fn) key on your keyboard.
It costs only 18 US Dollars, and I bought it from DealExtreme: here is the link , some pretty good reviews. Please consider that most stuff on there site is cheap Chinese garbage ;) free shipping included (amazing, I think that the Government stimulates export or something in Honk Kong by paying the postal fee).
Really a bargain if you ask me. In fact I like the keyboard so much that after testing (With Chinese stuff you have to do your own QC) it’s still hooked up instead of my regular keyboard. The much better quality Cherry G80 3000L with MX blue keyswitches (tikker the tik), for the moment i use this no-brand 78 keyboard as my main one. It’s stylish!
The problem, it has 78 keys (vs normal 104 keys US layout ones) and no insert key to be found. lets fix this!
I really like Microsoft’s disk based backup software:”Data Protection Manager 2010″. It doesn’t have the fancy features which the grown-ups like backup-exec, ARCserver do have. But these features where hard to manage and use anyway. DPM got all the basic functions and a simple layout and works. I 
have never looked back since i switched from those old fashioned (virtual) tape library backup solutions. I still think it’s a quick hack for them to create a (virtual) tape libary and say it’s a harddisk based backup solution. It needs a architecture changes under the hood to truly use the advantages of disk bases backups.
And for half the cost DPM is a no brainer if you prefer a simple, clean and workable backup solution for a medium sized company.
But we were having some troubles backing up the “system state” of a Windows 2008R2 though our Microsoft DPM 2010 backup server. Our DPM server reported the following error in its console (and eventviewer):
The replica of System Protection on dc1.******.local is inconsistent with the protected data source. All protection activities for data source will fail until the replica is synchronized with consistency check. (ID: 3106)
DPM cannot create a backup because Windows Server Backup (WSB) on the protected computer encountered an error (WSB Event ID: 517, WSB Error Code: 0x80070040). (ID: 30229)
Hello Word, this is my first post.
Dit is een html code block
Vol met stuff. Wat een hele lange regel gaat worden odat we line breaks gaan zien
E dit valt buiten de span style marktup
bron: hup