Greatest Hits

63
votes
3answers
89k views

Is there a way to view the members of an Active Directory group if you aren't a domain admin and can't log into to a domain controller?

Is there a way to view the members of an Active Directory group if you aren't a domain admin and can't log into to a domain controller?
18
votes
6answers
67k views

How can I edit the welcome message when ssh start?

I have a vps for my website hosting. It is running a ubuntu server. Every time I logged in my server by ssh, it displays a lengthy welcome message in my terminal. Linux node61.buyvm.net ...
28
votes
7answers
131k views

Disable password complexity rule in Active Directory

Where do I go to disable the password complexity policy for the domain? I've logged onto the domain controller (Windows Server 2008) and found the option in local policies which is of course locked ...
75
votes
9answers
78k views

Shell command to monitor changes in a file - What's it called again?

I know there was a command on Unix that I could use to monitor a file and see changes that are getting written to it. This was quite useful especially for checking log files. Do you know what it is ...
159
123
votes
2answers
49k views

How do I select which Apache MPM to use?

I'm a little confused between the different MPMs offered by Apache - 'worker', 'event', 'prefork', etc. What are the major differences between them, and how can I decide which one will be best for a ...
54
votes
4answers
158k views

How can I port forward with iptables?

I want connections coming in on ppp0 on port 8001 to route to 192.168.1.200 on eth0 on port 8080 I've got these two rules -A PREROUTING -p tcp -m tcp --dport 8001 -j DNAT --to-destination ...
58
votes
7answers
90k views

how to check if a library is installed?

In linux, how do I check if a library is installed or not? (from the command line of course). In my specific case now, I want to check whether libjpeg is installed.
37
votes
2answers
83k views

DNS - NSLOOKUP what is the meaning of the non-authorative answer?

When I do a NS Lookup, for some domains I get the reply saying Non-authorative answer:. I want to know what it means? Got answer: HEADER: opcode = QUERY, id = 3, rcode = NXDOMAIN ...
12
votes
4answers
51k views

Best way to gracefully restart CentOS?

I always used the command: shutdown -r now However, sometimes that causes MySQL issues. What's the most graceful way to restart CentOS? I've seen: reboot and halt How can I gently reboot ...
32
votes
11answers
84k views

create home directories after create users

I created some users with: $ useradd john and I forgot to specify the parameter -m to create the home directory and to have the skeleton files copied to each user. now I want to do that, and I ...
78
votes
13answers
85k views

How to reconnect to a disconnected ssh session

Is there a way to connect to an ssh session that was disconnected? We are having problems with our network connection to a remote site that we are working on separately; however, in the mean time we ...
12
votes
9answers
92k views

Windows File and Folder “Attributes” A or C

In Windows Server 2003, in the "Attributes" column of windows explorer, some files have "A" or "C" or "AC" or others. What do these mean?
22
votes
6answers
84k views

How do I access the list of currently logged on users through Terminal Services Manager in Windows Server 2012?

In Windows 2003 and 2008 we had Terminal Services Manager (see screenshot below). However in Windows server 2012 it's gone. Does anyone know how to access the list of currently remotely logged on ...
49
votes
14answers
136k views

What is the correct temperature for a server room?

When I was working in our server room, I noticed that it was very cold. I know that the server room has to be cold to offset the heat of the servers, but perhaps it is TOO cold. What is an ...
82
votes
9answers
92k views

When does `cron.daily` run?

When do entries in cron.daily (and .weekly and .hourly) run, and is it configurable? I haven't found a definitive answer to this, and am hoping there is one. I'm running RHEL5 and CentOS 4, but for ...
43
votes
8answers
60k views

hosts file ignored, how to troubleshoot?

The hosts file on Windows computers is used to bind certain name strings to specific IP addresses to override other name resolution methods. Often, one decides to change the hosts file, and discovers ...
43
votes
3answers
63k views

What is the difference between unicast, anycast, broadcast and multicast traffic?

I have never had the privilege of working in an environment that required complicated routing or if it did require it, it was handled upstream of me. I've always used very simple static routing ...
109
votes
14answers
60k views

How do diff over ssh?

How do I diff files/folders across machines provided that the only connectivity available is ssh?
153
75
votes
6answers
144k views

Boot and Install Windows from a USB thumb drive

Installing Windows from a thumb drive is vastly superior to burning a copy to a DVD which will fill some landfill somewhere with toxic stuff. Not to mention it's about 50x faster to install Windows ...
2
votes
7answers
26k views

Can't start CentOS 7 “network” service

I Can't start CentOS 7 "network" service after disabling and removing "NetworkManager" service. When I check the network service status, it comes up with the following error: #systemctl status ...
17
votes
3answers
43k views

Debian 5.0 (lenny) apt sources fail?

For the past few days, I couldn't update our apt-sources on Debian 5.0 (lenny). I get the following errors. W: Failed to fetch http://ftp.debian.org/debian/dists/lenny/main/binary-amd64/Packages 404 ...
45
votes
5answers
16k views

On a dual CPU server, is it normal for one CPU to run hotter than the other?

I have a dual Opteron server running Linux with libvirt to host several VMs. The VMs work fine and the server processes OK, but I notice one CPU always runs about 69C (throttles at 70C) and the other ...
40
votes
7answers
70k views

df in linux not showing correct free space after file removal

I have file servers which are used to store files. Files might reside there for a week, or for a year. Unfortunately, when I remove files from the server, df command doesnt reflect the freed up space, ...
25
votes
10answers
99k views

Group Policy installation failed error 1274

I'm trying to deploy an MSI via the Group Policy in Active Directory. But these are the errors I'm getting in the System event log after logging in: The assignment of application XStandard from ...
4
votes
4answers
48k views

SSH: Permission denied (publickey,gssapi-with-mic,password)

==================================================================== UPDATE: It turned out the configuration of sshd on host2 wont allow password login. Thanks to people answered this. Also don't ...
7
votes
5answers
94k views

Cannot enable network discovery on Windows Server 2008 R2

I'm trying to enable the Network Discovery feature on a newly installed Windows Server 2008 R2 instance. The network connection is in the Home or Work profile (it is not domain joined). These are the ...
92
votes
8answers
79k views

How can I run Debian stable but install some packages from testing?

Say you're running a server and you don't want to upgrade to Testing (Squeeze) from Stable (Lenny) to just install a required package or two. What's the best way of installing only certain packages ...
26
votes
6answers
60k views

How to Unban an IP properly with Fail2Ban

I'm using Fail2Ban on a server and I'm wondering how to unban an IP properly. I know I can work with IPTables directly: iptables -D fail2ban-ssh <number> But is there not a way to do it with ...
24
votes
4answers
81k views

Get directory containing the currently executed batch script

I use %0 in batch file to get the containing directory of the batch file but the result is :- c:\folder1\folder2\batch.bat I want just directory, without batch file name, like this :- ...
92
votes
14answers
80k views

In my /etc/hosts/ file on Linux/OSX, how do I do a wildcard subdomain?

I need to test sub-domains on my localhost. How can I effectively have this result of adding *.localhost.com to my /etc/hosts/ file? If it's not possible, how do I work around this problem? I need ...
61
votes
3answers
77k views

How to add dependency on a Windows Service AFTER the service is installed

I have a Windows Service that makes use of a SQL Server database. I don't have control over the installation of the service, but would like to add a dependency on the service to ensure that it starts ...
14
votes
9answers
118k views

Disable TeamViewer from “stealing” Port 80?

How can you disable TeamViewer from using/reserving port 80? I am certain in the previous version <v4.1.6 there used to be a radio button option in "options" which disabled it from needing it, but ...
10
votes
1answer
40k views

How to stop ping output?

I run ping <hostname> command in console and it now outputs hundreds of those rows now (icmp_seq=526 ttl=64 time=0.026 ms), icmp_seq is like 500 or more now. How to stop it? (linux debian) ...
34
votes
13answers
64k views

How to create an SHA-512 hashed password for shadow?

The previous SF questions I've seen have lead to answers that produce MD5 hashed password. Does anyone have a suggestion on to produce an SHA-512 hashed password? I'd prefer a one liner instead of a ...
29
votes
14answers
72k views

What is a patch panel?

What is a patch panel? How it is different from (layer 2) switch? EDIT: I think my primary question (and confusion) is this: Why don't network connections go straight to the switch? Don't we still ...
18
votes
4answers
109k views

Which ports do I need to open in the firewall to use NFS?

I'm running Ubuntu 11.10 - setting up NFS to share a directory among many other servers. Which ports are required to be opened on the firewall?
16
votes
4answers
22k views

How do I patch RHEL 4 for the bash vulnerabilities in CVE-2014-6271 and CVE-2014-7169?

A mechanism for remote code execution through Bash has been widely reported yesterday and today (September 24, 2014.) http://seclists.org/oss-sec/2014/q3/650 Reported as CVE-2014-7169 or CVE-2014-6271 ...
58
votes
9answers
69k views

How can I export the privileges from MySQL and then import to a new server?

I know how to export/import the databases using mysqldump & that's fine but how do I get the privileges into the new server. For extra points, there are a couple of existing databases on the new ...
182
votes
9answers
28k views

Heartbleed: What is it and what are options to mitigate it?

This is a Canonical Question about understanding and remediating the Heartbleed security issue. What exactly is CVE-2014-0160 AKA "Heartbleed"? What is the cause, what OSs and versions of OpenSSL ...
31
votes
8answers
103k views

How can I get a list of shared directories on local Windows server?

If I have a Windows server (typically 2000, 2003 or 2008), is there a simple way to list all local directories shared on that server? I can find the shares themselves easily enough, but I would love ...
36
votes
4answers
93k views

Adding a directory to $PATH in CentOS?

We just got our new server(s) up and we're running CentOS on them all. After successfully installing Ruby Enterprise Edition, I would now like to add the REE /bin (located at ...
122
votes
16answers
105k views

Why is DNS failover not recommended?

From reading, it seems like DNS failover is not recommended just because DNS wasn't designed for it. But if you have two webservers on different subnets hosting redundant content, what other methods ...
66
votes
15answers
62k views

Showing total progress in rsync: is it possible?

I have searched for this option already, but have only found solutions that involve custom patching. The fact that it does not show in --help and no more info can be found probably indicates the ...
118
377
votes
13answers
70k views

How do I deal with a compromised server?

This is a Canonical Question about Server Security - Responding to Breach Events (Hacking) See Also: Tips for Securing a LAMP Server Reinstall after a Root Compromise? Canonical ...
37
votes
2answers
95k views

What are windows 7 N/KN/VL editions?

We're subscribed to MSDN at work and I've noticed that among the various windows "editions" there are downloads such as "Windows 7 Ultimate N" and "Windows 7 Ultimate N and KN". What are these ...
1
vote
7answers
111k views

User Profile keeps loading TEMP Profile

I am having a difficult time with an issue that our support staff won't support (as they will not support Vista). I am able to log into our domain without any issue, however, when I go home and log ...
100
30
votes
5answers
92k views

Proxy Error 502 “Reason: Error reading from remote server” with Apache 2.2.3 (Debian) mod_proxy and Jetty 6.1.18

Apache is receiving requests at port :80 and proxying them to Jetty at port :8080 The proxy server received an invalid response from an upstream server The proxy server could not handle the request ...
50
votes
8answers
71k views

How to tell if a Linux system is big endian or little endian?

I know that certain processors are Big Endian and others are Little Endian. But is there a command, bash script, python script or series of commands that can be used at the command line to determine ...
114
18
votes
3answers
126k views

How to properly set permissions for NFS folder? Permission denied on mounting end.

I'm trying to connect to an NFS folder on my dev server. The owner of the folder on the dev server is darren and group darren. When I export and mount it to my Mac using the Disk Utility it mounts, ...
114
votes
9answers
55k views

Keeping a linux process running after I logout

I'm connecting to a Linux machine through SSH, and I'm trying to run a heavy bash script that makes filesystem operations. It's expected to keep running for hours, but I cannot leave the SSH session ...