Linux Networking

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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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hi how can i do this in linux ubunt disabled NIPS protection (low and middle severity)
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Dear Experts
We have to setup syslog server for the centralized logging of all network equipment’s and servers in my network, please suggest solution for the same can we setup in linux or windows, thanks in advance.
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Dear All,


               How do i create below rule port forward by using command mode ? any help would be appreicated, Thanks


1

Keith
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ansible error

[root@ansible ansible]# vim site.yml
---
- hosts: web03.cioft.com
  roles:
    - apache

tasks:
  - name: Allow HTTPD traffic
    firewalld:
      service: https
      permanent: yes
      state: enabled


#tasks:
# - name: Allow httpd traffic
#command: firewall-cmd --zone=dmz --permanent --add-service=http --add-service=https
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This mean the host you are running does not have the necessary Python library to run the nmcli module. Please open a new question for the library issue
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I am trying update a new ip details to my webserver using ansible.
Here is my playbook. I am getting following error.

[root@ansible playbooks]# ansible-playbook network.yml
ERROR! Syntax Error while loading YAML.
  did not find expected key

The error appears to be in '/opt/playbooks/network.yml': line 4, column 3, but may
be elsewhere in the file depending on the exact syntax problem.

The offending line appears to be:


  - name:  IP configuration
  ^ here


---
- hosts: webservers

  - name:  IP configuration
    nmcli:
      conn_name: my-eth1
      ifname: ens160
      type: ethernet
      ip4: 192.168.2.153/24
      gw4: 192.168.2.1
      state: present
1
hi no internat in my ubuntu vm
internat32
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hi am not able to connect to my vm via putty
putty
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hi am not able to ssh
ssh
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hi am having this error starting my solaris/unix
ipaddr
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I have setup Icinga2 on an Ubuntu server and have it monitoring the local host and several servers and switches for HostAlive.   I would like to expand this to monitor diskspace and important services on the Windows servers but I am having issues getting this working.   I would also like to change the notification interval for apt to something other than the default but I do not see how to set a custom interval for just the apt service.

How do I configure Icinga2 to monitor Windows Disks/services?     Currently I have the following in my conf files.   What it is showing is the disks on the Ubuntu server and not the  Windows server.

hosts.conf

object Host "Server1" {
        /* Set custom attribute `os` for hostgroup assignment in `groups.conf`. */
        vars.os = "Windows"
        import "generic-host"
        address = "192.168.1.21"
        check_command = "hostalive"
        /* notify command */
        vars.notification["mail"] = {
           groups = [ "icingaadmins" ]
         }
  /* Define disks and attributes for service apply rules in `services.conf`. */
  vars.disks["disk"] = {
    /* No parameters. */
  }
  vars.disks["disk /"] = {
    disk_partitions = "/"
  }
}



services.conf

apply Service for (disk => config in host.vars.disks) {
  import "generic-service"

  check_command = "disk"
  vars += config
}



Lastly I am getting spammed with apt notifications.   I would like to receive notifications for apt once a day or …
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Have 3 nics in system

Eth0
Eth1
Eth2

How can I route

 traffic related to x.x.x.x IP on eth0

Traffic to y.y.yy on eth1
Traffic to a.a.a.a on eth1

Traffic to z.z.z.z on eth2
Traffic to q.q.q.q on eth2

Using redhat system
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hi am having this error starting my linux vm in virtual box
vmerror
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Upgraded from Samba 4.8.3 to Samba 4.9.1 on RHEL 7.  Now, guest account shares do not appear to be working the same (or at all).  I need some precise assistance with a Samba expert for the required smb.conf changes to get us back to working like we have been for the past 10 years.
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hi am not having internat in my vm is oracle linux
internatssh32
am runing vm in virtual box
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hi am having this error starting my virtual box
errorvmerro213.jpg
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I am trying to send email using email relay server which I have setup on postfix.


[root@email postfix]# mailq
-Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient-------
C7792185E7F1      451 Sun Sep  8 15:27:48  root@email.mydomain.com
(SASL authentication failed; cannot authenticate to server mail01.mydomain.com[x.x.x.x]: no mechanism available)
                                         user@gmail.com

60870185E7F2      451 Sun Sep  8 16:52:57  root@email.mydomain.com
(host mail01.mydomain.com[x.x.x.x] said: 454 4.7.1 <user@gmail.com>: Relay access denied (in reply to RCPT TO command))
                                         user@gmail.com
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I am running Redhat 6.9 and i am investgating an intermittent connectivity problem with a health checking ping between an F5 loadbalancer and a vmware virtual server running Redhat 6.9

The server is showing in the vmware log vmsvc that the max number of static routes 100 has been reached. However, the max_size for the routing cache is 8388608. Do you know if this kernel setting for the max size in the routing table is the same as the max. routes in the routing table?  I have googled the vmsvc error and apparently upgrading to a later version of the package gets rid of the errors but I'd also like to understand the setting for the maximum number of static routes allowed on a Redhat server.

cat /proc/sys/net/ipv4/route/max_size
8388608

Thanks for any assistance with this.
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unable to access web site. port 80 still blocked

[root@logserver log]# iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere            state RELATED,ESTABLISHED
ACCEPT     icmp --  anywhere             anywhere
ACCEPT     all  --  anywhere             anywhere
ACCEPT     tcp  --  anywhere             anywhere            state NEW tcp dpt:ssh
REJECT     all  --  anywhere             anywhere            reject-with icmp-host-prohibited
ACCEPT     tcp  --  anywhere             anywhere            state NEW tcp dpt:http
ACCEPT     tcp  --  anywhere             anywhere            state NEW tcp dpt:https

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination
REJECT     all  --  anywhere             anywhere            reject-with icmp-host-prohibited

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
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what is WWPN number and how do i get this number in a redhat linux machine?
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I have a linux cloud based database server where users export reports to a folder on the server.  That folder is shared using samba and can be accessed from our windows network (VPN connection).  Instead of having users directly access the linux samba share I would like to monitor that share and copy any files over to a windows server on the local network as they show up.  The files can then be deleted from the linux folder after some time period, but still be available to the users on the windows server.  Preferably this would be a program that runs on the windows server as a service so I don't have to be logged in.  I have tried a couple of programs (robocopy, AutomationWorkshop, ViceVersa Pro) and they work if I am copying the files manually, but don't work in automatic mode as a service.  They don't seem to be able to find the samba share if I am not logged in.  I'm guessing that it has to do with drive mapping being tied to the user login.  Looking for some good method of automatically bringing these files onto the local windows server.
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Hello dear friends
I need your help with configuring encryption between web browser and proxy server (SQUID)
I have working squid on vps with ncsa authorization but I don’t know how to encrypt traffic  between proxy client and server. I don’t want to use vpn or http tunnel for it. Plz help.
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[user@ansible01 install]$ ssh-copy-id web01.cifot.com
/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/home/user/.ssh/id_rsa.pub"
/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
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My attempts to build iptables rules are failing and I need some help.

I have two external IP addresses (27.92.104.166, 27.92.104.164 - not the real ip addresses...) that will send traffic on tcp port 30505 to my network on its external interface (28.29.28.72 - also not real) which needs to be forwarded to an internal server (10.17.2.9 listening on port 8080).

I started with a simple INPUT rule

iptables --append INPUT --match tcp --protocol tcp --src 27.92.104.166 --sport 30505 --dst 10.17.2.9 --dport 8080 --jump ACCEPT
iptables --append INPUT --match tcp --protocol tcp --src 27.92.104.164 --sport 30505 --dst 10.17.2.9 --dport 8080 --jump ACCEPT

Open in new window


But this is not enough since I also need some kind of FORWARD rule and perhaps a PREROUTING rule, and NAT may play some kind of part in this as well.  There are tons of sites out there with examples that do not match my case so I am floundering in the dark.

I am trying to learn iptables as quickly as I can but can someone point me in the right direction on this particular case?

Many thanks!
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Hello,

I am running Debian 9 on Server 2012 R2 Hyper-V. The scnario is that I have 2 physical servers each with a Debian virtual machine.

A) Setup Hyper-v for mirroring

1) The goal is to capture packets so Hyper-v on both is set in monitoring mode.

2) Once the "Destination" settings under the virtual machine network adapter for mirroring is set in the Hyper-v configuration.
I immediately notice that the physical network interface on the server (for the Hyper-v virtual switch) starts increasing rapidly say 70 Mb/s ON BOTH Servers...
 this is good it means that the Hyper-v settings are sane (and of course the Network Configuration on the switch is perfect).

B) Setup Debian for promiscuous mode

1) Here I use:

allow-hotplug eth1
               iface eth1 inet manual
               up ifconfig eth1 promisc up
              down ifconfig eth1 promisc down

Open in new window


and verify with ifconfig as shown below

Debian VM1 on Server1
eth1: flags=4419<UP,BROADCAST,RUNNING,PROMISC,MULTICAST>  mtu 1500
        ether 00:15:5d:15:16:17  txqueuelen 1000  (Ethernet)
        RX packets 5090918  bytes 3090553169 (2.8 GiB)
        RX errors 0  dropped 6  overruns 0  frame 0
        TX packets 89  bytes 7638 (7.4 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Debian VM2 on Server2
eth1: flags=4419<UP,BROADCAST,RUNNING,PROMISC,MULTICAST>  mtu 1500
        ether 00:15:5d:15:16:17  txqueuelen 1000  (Ethernet)
        RX packets 42094  

Open in new window

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Linux Networking

18K

Solutions

15K

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.