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The variety of Linux distributions creates myriad issues relating to configuration and operations when computers are networked, not the least of which is the use of various network management applications, some of which are included with specific distributions, while others are standalone applications.

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I have a Asus RT-N18U router. (but can buy another one), with DD-WRT firmware DD-WRT v3.0-r32170 std (06/01/17)
I want:
Hotspot for Restaurants that:
-People connect (no password) to WIFI
-they get a webpage (can be on router or in internet)
-webpage ask for emailadress
-once introduced emailadress and send it (to a server in internet with its MAC address) they get granted lets say 2 hours of internet
-after 2 hours they have to come back to the login page again (or better they get blocked for 10 hours with error webpage and after to login page again)
-no other service (not free and not payed) should be used

-the router mentioned offers dd-wrt with onboard radiusserver (I tried it and works), chillispot or nocatsplash (both I didn't get to work)
The router should be configured (WAN) as DHCP automatic conection and he should use his own network with his own DHCP server (so it is easy to connect him to an existing network)

I need somebody who configures the router and tell me how the configuration works. (where are modifyable files)
0
Windows Server 2016: All you need to know
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Windows Server 2016: All you need to know

Learn about Hyper-V features that increase functionality and usability of Microsoft Windows Server 2016. Also, throughout this eBook, you’ll find some basic PowerShell examples that will help you leverage the scripts in your environments!

hi trying to install jboss on AWS ubunutu and access console from external/Internet

Followed so far
1. Installed Jboss on ubuntu followed these page (https://www.digitalocean.com/community/tutorials/how-to-install-jboss-on-ubuntu-12-10-64bit)
2. Followed this step to allow connections from external (http://technicles.com/how-to-make-your-jboss-or-wildfly-as-remotely-accessible/)
3. started with -b
./standalone.sh -b 0.0.0.0
./standalone.sh -b <AWS Elastic IP>

when I tried to connect I get below error on the browser
This site can’t be reached.<AWS Elastic IP> refused to connect.


after I enabled TRACE. I get more info but couldn't figure out what is wrong. Please help
Pls check the attached trace.log file

thanks in advance
trace.log
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Dear Experts,

We have automout enabled for our /home directory, Whenever a user login to the servers automout triggers NFS mount to use to mount  home directory[/auto/home/<username>] in the servers.  The NFS servers hosted on Netapp storage device.

Below is the logs from messages file:
automount[25639]: mount(nfs): nfs: mount failure 10.x.x.x:/vol/m1_ldap_home/localhome/sivakumar on /auto/home/sivakumar
Jun  8 09:20:30 xxxxxxxxx automount[847]: attempting to mount entry /auto/home/sivakumar
Jun  8 09:20:51 xxxxxxxxx automount[25644]: >> mount: RPC: Timed out.

My Observation:

The NFS client servers which NOT in the same network where NFS Server is , having above problems.

I need to know , what angle i need to troubleshoot this issue, how to resolve and what is solution?

Thanks in advance.

Sk..
0
Good Morning!

What does the following two options actually do for DHCPd and does it work with failover?

allow booting;
allow bootp;


Im trying to configure DHCPd Failover and from what Im reading Im not quite sure if DHCP scopes that need PXE boot will work with DHCPd Failover. I believe the two options listed above would be needed but I dont know.  If so, should they be added in the primary and secondary dhcpd.conf files or the dhcpd.master?

Also the two options below -- are they also needed and should they be added in the primary and secondary dhcpd.conf files or the dhcpd.master too?

next-server x.x.x.x;
filename "xxx";

Thanks in advance!

Primary dhcpd.conf file
#authoritative;
ddns-update-style none;
ignore client-updates;
one-lease-per-client true;
omapi-port 7911;

#Failover peer section
failover peer "dhcp-partner" {
  primary;
  address server1.paychex.com;
  port 647;
  peer address server2.paychex.com;
  peer port 647;
  max-response-delay 60;
  max-unacked-updates 10;
  mclt 3600;
  split 153;
  load balance max seconds 3;
}
include "/etc/dhcp/dhcpd.master";

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Secondary dhcpd.conf file
#authoritative;
ddns-update-style none;
ignore client-updates;
one-lease-per-client true;
omapi-port 7911;

#Failover peer section
failover peer "dhcp-partner" {
  secondary;
  address server2.paychex.com;
  port 647;
  peer address server1.paychex.com;
  peer port 647;
  max-response-delay 60;
  max-unacked-updates 10;
  load balance max seconds 3;
}
include "/etc/dhcp/dhcpd.master";

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dhcpd.master file
option domain-name "example.com";
allow booting;
allow bootp;
next-server x.x.x.x;
filename "xxx";
option option-242 code 242 = string;

#dhcpd wants to listen on its own networks
subnet 17.8.4.0 netmask 255.255.252.0 {
  ignore unknown-clients;
}

#dhcpd wants to listen on its own network
subnet 19.4.8.0 netmask 255.255.252.0 {
  ignore unknown-clients;
}

#Scope [12.4.4.0] TEST PXE Boot
subnet 12.4.4.0 netmask 255.255.252.0 {
  option subnet-mask 255.255.252.0;
  option routers 12.4.4.1;
  option domain-name-servers 12.2.2.198;
  pool {
    failover peer "dhcp-partner";
    default-lease-time 300;
    max-lease-time 360;
    range 12.4.5.0 12.4.5.255;
  }
}

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We had our master DNS server go down last night for our domain (RAID failure). Technically our secondary DNS server should have picked up the slack, however for one domain where our DNS server holds the records for an externally hosted mail server of ours, it was unresponsive until we made NS2 our master server.

The biggest issue is why a secondary server would not show as responsible until becoming a master whereas other services on our network were fine...

Any ideas why this would be the case?
CentOS 7 - BIND.
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I have one 12U1 SLES machine in which i want to open an port no 31015 for SAP HANA but unable to.

Netstat -tulpn also not showing LISTEN to this port .

I have also tried it with Yast2 firewall advance option but dont same problem

Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      2475/sshd
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      2169/master
tcp        0      0 0.0.0.0:51013           0.0.0.0:*               LISTEN      2341/sapstartsrv
tcp        0      0 0.0.0.0:51014           0.0.0.0:*               LISTEN      2341/sapstartsrv
tcp        0      0 0.0.0.0:1128            0.0.0.0:*               LISTEN      2295/sapstartsrv
tcp        0      0 0.0.0.0:1129            0.0.0.0:*               LISTEN      2295/sapstartsrv
tcp        0      0 :::22                   :::*                    LISTEN      2475/sshd
tcp        0      0 ::1:25                  :::*                    LISTEN      2169/master
udp     5376      0 0.0.0.0:68              0.0.0.0:*                           1308/wickedd-dhcp4


telnet IP 31015
gives keep trying then unable to reach

telnet working for other ports like ssh and 1128 etc.

please help
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I need to connect a Virtual Machine hosted somewhere running CentOS 6 to a client which is allowing connection through VPN only. However I have almost no knowledge about VPNs. The client has given me following info for connection:

VPN Remote Endpoint: <IP Address given by the client>
VPN Hardware: NGX R75.45 (SPLAT)

IKE (Phase 1)
==================
Authentication Method: Pre shared key (TBA)
DIffie-Hellman group: DH-2
Encryption Algorithm: AES-128
Hashing Algorithm: SHA-1
Renegotiate IKE: 14400 seconds

IPSEC (phase 2)
======================
Encryption Algorithm: AES-128
Hashing Algorithm: SHA-1
Renegotiate IKE: 3600 seconds
PFS Enabled: Yes

I am not sure where to put all these info in CentOS to make it to connect to the client's network.

I will be much thankful for any help.
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when i start the tomcat service i get this error.

server[3387]: May 29, 2017 2:33:36 PM org.apache.coyote.ajp.AjpMessage processHeader
server[3387]: SEVERE: Invalid message received with signature 18245
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Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:sunrpc          0.0.0.0:*               LISTEN      1/systemd
tcp        0      0 0.0.0.0:8817            0.0.0.0:*               LISTEN      5308/mongod
tcp        0      0 0.0.0.0:ssh             0.0.0.0:*               LISTEN      652/sshd
tcp        0      0 localhost:smtp          0.0.0.0:*               LISTEN      907/master
tcp        0      0 localhost:32000         0.0.0.0:*               LISTEN      2418/java
tcp        0      0 localhost:27017         0.0.0.0:*               LISTEN      1797/mongod
tcp6       0      0 [::]:monkeycom          [::]:*                  LISTEN      2418/java
tcp6       0      0 [::]:sunrpc             [::]:*                  LISTEN      1/systemd
tcp6       0      0 [::]:webcache           [::]:*                  LISTEN      3387/java
tcp6       0      0 [::]:http               [::]:*                  LISTEN      4534/httpd
tcp6       0      0 [::]:ssh                [::]:*                  LISTEN      652/sshd
tcp6       0      0 [::]:ddi-tcp-1          [::]:*                  LISTEN      28290/node
tcp6       0      0 localhost:smtp          [::]:*                  LISTEN      907/master
tcp6       0      0 [::]:https              [::]:*                  LISTEN      4534/httpd
tcp6       0      0 localhost:mxi           [::]:*                  LISTEN   …
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[root@web02 ~]# cat /etc/*-release
CentOS release 6.8 (Final)
LSB_VERSION=base-4.0-amd64:base-4.0-noarch:core-4.0-amd64:core-4.0-noarch
CentOS release 6.8 (Final)
CentOS release 6.8 (Final)

[root@web02 ~]# yum info -v apache-tomcat-apis
Loading "fastestmirror" plugin
Config time: 0.076
Yum Version: 3.2.29
rpmdb time: 0.000
Setting up Package Sacks
Loading mirror speeds from cached hostfile
 * base: centos.mirror.rafal.ca
 * extras: centos.mirror.rafal.ca
 * updates: ca.mirror.babylon.network
pkgsack time: 0.126
Installed Packages
Name        : apache-tomcat-apis
Arch        : noarch
Version     : 0.1
Release     : 1.el6
Size        : 246 k
Repo        : installed
From repo   : base
Committer   : Andrew Overholt <overholt@redhat.com>
Committime  : Tue Feb  2 07:00:00 2010
Buildtime   : Wed Nov 10 19:18:17 2010
Install time: Sun May 28 11:58:23 2017
Installed by: root <root>
Changed by  : System <unset>
Summary     : Tomcat Servlet and JSP APIs
URL         : http://tomcat.apache.org/
License     : ASL 2.0
Description : Apache Tomcat's Servlet 2.4/JSP 2.0 and Servlet 2.5/JSP 2.1 APIs.

[root@web01 ~]# cat /etc/redhat-release
CentOS Linux release 7.3.1611 (Core)

[root@web01 ~]# yum info -v apache-tomcat-apis
Loading "fastestmirror" plugin
Config time: 0.009
Yum version: 3.4.3
rpmdb time: 0.000
Setting up Package Sacks
Loading mirror speeds from cached hostfile
 * base: centos.mirror.globo.tech
 * extras: centos.bhs.mirrors.ovh.net
0
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Hi everyone, I would like to have outputs of tcpdump in standard structure. Like below:

05:49:56.604899 00:00:00:00:00:02 > 00:00:00:00:00:03, ethertype IPv4 (0x0800), length 10202: 10.0.0.2.54880 > 10.0.0.3.5001: Flags [.], seq 3641977583:3641987719, ack 129899328, win 58, options [nop,nop,TS val 432623 ecr 432619], length 10136
05:49:56.604908 00:00:00:00:00:03 > 00:00:00:00:00:02, ethertype IPv4 (0x0800), length 66: 10.0.0.3.5001 > 10.0.0.2.54880: Flags [.], ack 10136, win 153, options [nop,nop,TS val 432623 ecr 432623], length 0
05:49:56.604900 00:00:00:00:00:02 > 00:00:00:00:00:03, ethertype IPv4 (0x0800), length 4410: 10.0.0.2.54880 > 10.0.0.3.5001: Flags [P.], seq 10136:14480, ack 1, win 58, options [nop,nop,TS val 432623 ecr 432619], length 4344

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However it is important for me that all these structured information saved in 10 files with size of 10 MB. I know that I have to use this command:

tcpdump -i h1-eth0 -w /tmp/trace.txt -W 10 -C 10 -K -n

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However the problem is that, the out put is not in standard way. Can you please help me to find a single command that gives me the standard out put of the tcpdump in 10 files with size of 10 MB?
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in Unix

what is the meaning of below command



zgrep 'RPT|O|GetProducts' xyz.gz meaning
why we need RPT|o|
in the beginning what is the meaining of pipe here?
please advise
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i downloaded driver from tp-link site.but i don't know how to install it? tell me step by step. or another solution for driver installation.
0
Unable to copy or move files in a linux folder into a mounted mapped network drive.  Getting error file or directory does not exist but yet it does and can display files in the shared folder.
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i have the following connection. i did clone a server and i would like to see whats running so i can stop those daemon on the cloned VM.
what is the best way to tell which app or service running?


Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program name
tcp        0      0 127.0.0.1:8005              0.0.0.0:*                   LISTEN      1890/java
tcp        0      0 0.0.0.0:8009                0.0.0.0:*                   LISTEN      1890/java
tcp        0      0 127.0.0.1:27017             0.0.0.0:*                   LISTEN      2013/mongod
tcp        0      0 0.0.0.0:60333               0.0.0.0:*                   LISTEN      1300/rpc.statd
tcp        0      0 0.0.0.0:111                 0.0.0.0:*                   LISTEN      1278/rpcbind
tcp        0      0 0.0.0.0:8080                0.0.0.0:*                   LISTEN      1890/java
tcp        0      0 0.0.0.0:80                  0.0.0.0:*                   LISTEN      1942/httpd
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      1731/sshd
tcp        0      0 127.0.0.1:631               0.0.0.0:*                   LISTEN      1499/cupsd
tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      1813/master
tcp        0      0 0.0.0.0:443                 0.0.0.0:*                   LISTEN      1942/httpd
tcp        0      0 ip:60288   …
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My Samba shares recently went missing. After some quick troubleshooting I found that its lost connectivity with the AD servers. The result of a 'net ads info' No login servers.   Since this has been working for sometime now I looked for recent changes. The only significant change is the my 2008 R2 domain controllers installed Service Pack 1.  I saw an error stating that "my-server-name" failed to authenticate. Access is denied.

I removed the samba server from AD and then added it back in. i restarted samba services tried again to no avail. I then removed the client completely and reinstalled but the same error occurred.  I feel like this is AD related but can't discern a path to troubleshoot.
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We have been attempting for days now to join a Linux client to the Microsoft Active Directory domain.

The process we are using is located at:
https://wiki.archlinux.org/index.php/Active_Directory_Integration#Active_Directory_Configuration

When we get to the Join the Domain - using the command
net ads join -U Administrator

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We receive an error:
Failed to join domain: failed to lookup DC info for domain 'DOMAIN NAME' over rpc: Undetermined error

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Any help and more information about our configuration is available upon request.

Thanks,
Jim
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I am unable to ping a Linux Server on the same network from a windows server.

I can ping other Linux servers but not this particular one, and I cannot see anything different.

Please can someone advise on what to look at?
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I am using LAMP (Linux, Apache, MySQL, PHP) as my all in one production environment. Normally, I use MAMP (the Mac version of LAMP). The IT department of my employer set up a site in Ubuntu for me. They "defined" and "enabled" the root folder for my site. However, it appears if anything exists outside of the root folder, including other php files, I do not have access to it. For instance, I have a file structures similar to these:

root folder (which includes index.php)  ---> css folder ---> css files

root folder (which includes index.php) ---> php folder ---> php files (such as process-form.php)

How do I define other directories/folders in my site config file and enable them, so I can access them?

Mind you, ALL of this will have to be done through the MS-DOS Command Prompt.
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Create the perfect environment for any meeting
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You might have a modern environment with all sorts of high-tech equipment, but what makes it worthwhile is how you seamlessly bring together the presentation with audio, video and lighting. The ATEN Control System provides integrated control and system automation.

We have CentOS 7 server and Samba share/domain installed. The client machines are able to access the shared file from the server and I am able to join the clients to domain. But when I login to domain I get the "Logon service not available" error. Someone please help?
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Hi Experts

I have a customer that has Linux Centos 6.5 samba file server installed. (old server)
They also have another server that has Centos 7 samba file server installed. (new server)
My scope on the project is to migrate from old server to new server.
I'm not very good in Linux but I understand that it requires to create Linux users as well as samba user for file sharing permission.

What is the proper way to migrate shared folder to new server including [file and folder permissions] and [list of users(linux and samba)"]?
Example we can use Robocopy in Windows server to migrate permission, how about in Linux ? Could you please provide step by step ?


Thanks
0
Hello
How to turn on computer automatically from crontab in Cantos & Ubuntu ?
0
squid.conf.txt

I need to setup a proxy on a windows machine which should be running as https and I have to access https site via that proxy. I am okay to use Squid or any other proxy but not able to setup the conf file properly.

As far as I understand, only chrome browser provides capability of using https proxy so I want to test on chrome browser - opening some https page using https proxy. I will also like to understand that where will all certificates need to be imported for this to work.

I have attached my squid conf, for reference.

Thanks & Regards,
Ashish
0
Dear Colleagues,

I have brand new Ubuntu 16.04.2 LTS and I would like to understand how to add persistent route to it.

For real example I have a default route with metric 100 (see attachment) and I would like to make this route metric to 10.

Please shed some light to undertanding this concept.
default_routing_table.png
0
Hello
I am a beginner and I need help with squid proxy server configuration on ubuntu 12
After install I changed http_access allow all
That only what I did but when I use my proxy it is so slow knowing that server speed download about 500 MbPS and upload about 300 MbPS
And when I check my proxy with this site http://www.httptunnel.ge/ProxyChecker.aspx
It gives barely 5 KBPS while I used many proxies with high speed gives 30-40 KBPS.
So all I want is a config to increase proxy speed when I use and when I check.
Thank you
0

Linux Networking

17K

Solutions

3

Articles & Videos

14K

Contributors

The variety of Linux distributions creates myriad issues relating to configuration and operations when computers are networked, not the least of which is the use of various network management applications, some of which are included with specific distributions, while others are standalone applications.