Jul 30, 2013
tom

How do I make ssh fail rather than prompt for a password if the public-key authentication fails?

I’ve got a script that ssh’es several servers using public key authentication. One of the servers has stopped letting the script log in due to a configuration issue, which means that the script gets stuck with a “Password:” prompt, which it obviously cannot answer, so it doesn’t even try the rest of the servers in the list. Is there a way to tell the ssh client not to prompt for a password if key authentication […]

Continue Reading »
Jul 29, 2013
tom

What’s a good way to handle multiple devices with the same MAC address on one network?

The devices I’m working with come off the production line all set to the same MAC address. I can set each one to have their own static IP, and I’m wondering if there would be a way to connect them to the network at the same time in order to transmit configuration data (including a new MAC address) to them? I’ve got a Cisco SF 200-24 “Smart Switch”, and so far I’ve tried setting each […]

Continue Reading »
Jul 28, 2013
tom

Do I need to RAID Fusion-io cards?

Can I run reliably with a single Fusion-io card installed in a server, or do I need to deploy two cards in a software RAID setup? Fusion-io isn’t very clear (almost misleading) on the topic when reviewing their marketing materials Given the cost of the cards, I’m curious how other engineers deploy them in real-world scenarios. I plan to use the HP-branded Fusion-io ioDrive2 1.2TB card for a proprietary standalone database solution running on Linux. […]

Continue Reading »
Jul 27, 2013
tom

Why do my two ssh public keys have the same beginning?

I was updating the authorized_keys file on my server with the public key for the new laptop I got and I was surprised to discover that the two public keys began the same: # key 1 ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQ…. # # key 2 ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQ…. What’s the story on AAAAB3… etc? With some searching online, I see that others keys start the same, too. Does it explain the algorithm or version or something? Asked by Gabe […]

Continue Reading »
Jul 25, 2013
tom

Ethernet Frames and CSMA/CD [on hold]

I’m learning about Ethernet and I’m wondering if with several stations within the same Ethernet collision domain like pictured below, is it possible that a frame sent by station A is fully received by station B before a collision is detected (due to C or some other station also transmitting) and a jam signal is sent? In other words, can a station receive the same frame multiple times due to retransmissions? ———————– | | | […]

Continue Reading »
Jul 24, 2013
tom

DNS Resolution for example.com – Can you explain?

When I type mynewdomain.com into my browser I believe the following happens. My computer sends a request to my ISP’s name servers to find the IP address of mynewdomain.com My ISP name server sends a request to the “.” name server. The “.” sends a response back to the ISP name server, saying try using the com. nameserver. My ISP name server sends a request to the com. nameserver. The com. nameserver finds mynewdomain.com. and […]

Continue Reading »
Jul 23, 2013
tom

identifying emailids that flagged your email as spam

We send out emails to many people who may be interested selling old books. Some people ask us to remove them from our lists and we comply gladly. But some others simply flag our messages as spam. We want to remove these people from our lists too but how do we do this? Is there any API/service that we can use to identify these people and remove them from our lists? Asked by Dmartyn By […]

Continue Reading »
Jul 19, 2013
tom

Mouse cursor jumps around when using RDP

We have over 350 users complaining that their mouse cursor keeps jumping around when typing. It seems like it’s happening when the protocol is starved for bandwith, but I’m not quite sure yet. If it only was the cursor moving it would be fine – problem is that it also moves the focus so that they are suddenly writing text in a different place in the document without noticing too late (old people, they stare […]

Continue Reading »
Jul 19, 2013
tom

Can I use puppet on an existing Linux server?

I want to learn puppet but I am confused with one thing. I have already installed many python modules, apache modules, PHP plugins etc. Can I convert all that into puppet so that in my new server the puppet install them automatically? I am confused how will that work. I don’t remember which thing I installed or how I configured them. How do people do it? Asked by MOtaro Site Sure, you can do that. […]

Continue Reading »
Jul 16, 2013
tom

Cannot configure ETH1 on centos 6

I have a server running Centos 6.4. eth0 is configured and works fine with an internet (external to my LAN) address. I am attempting to configure eth1 with the following ifcfg-eth1 file: DEVICE=eth1 HWADDR=A4:BA:DB:14:E3:B8 TYPE=Ethernet ONBOOT=yes NM_CONTROLLED=no BOOTPROTO=static ipaddr=192.168.1.210 gateway=192.168.1.1 dns1=8.8.8.8 After I do an IFUP ETH1 command, I get an entry for it but no IPV4 address as shown in the following ifconfig output: eth0 Link encap:Ethernet HWaddr A4:BA:DB:14:E3:B7 inet addr:xxx.xxx.xxx.131 Bcast:xxx.xxx.xxx.143 Mask:255.255.255.240 inet6 […]

Continue Reading »
Pages:«1234567...5702»