Juniper ScreenOS for SSG security appliance can be managed either through the Web UI or command line interface (CLI). Upgrade through the Web interface can be endless and painful. The best way to do it is through the CLI. To accomplish this task, you’ll need : – SSH or Telnet client – TFTP server Here… Read More »
If you experience issue with your subnet or receiving the following message when you try to ping an IP address, this mean you have a routing loop on your network. The same subnet might be configured on another router and the network is confused due to the different destination. You need to remove the bad… Read More »
As you might noticed on latest version of Windows, ICMP requests are blocked by default with the built-in firewall. Use this simple command to enable echo request : netsh firewall set icmpsetting 8 enable
You might notice this error trying to add a static route to your Juniper switch stack : root@ir01# set routing-options rib inet.0 static route 0.0.0.0/00 next-hop 0.0.0.0 {master:0}[edit] root@ir01# commit synchronize [edit protocols] ‘bgp’ [edit protocols] ‘ospf3’ [edit routing-options rib inet.0 static] ‘route 0.0.0.0/00’ RT: DEST: 0.0.0.0 MASK: 255.0.0.0 mask too short error: configuration check-out… Read More »
Running large and high demanding hypervisor connected to SAN storage require jumbo (large MTU) frames to enhance I/O performance to the guests virtual machines. To achieve that, you need to use the command line since vSphere console do not allow to do such thing. 1. Stop all guest virtual machine and put the hypervisor in… Read More »
You may experience this error shown on “dmesg” or system logs (/var/log/messages) : IPv6 addrconf: prefix with wrong length 126 This actually indicate a device on your network trying to broadcast IPv6 information that dosen’t match your network configuration. To get rid and disable this, simply run the following commands as root : echo 0… Read More »
If you have a full subnet to add on RHEL/CentOS Linux system, there is a short way to achieve this instead of manually create single alias interfaces. 1. Create a script at this location : vi /etc/sysconfig/network-scripts/ifcfg-eth0-range0 (ajust values as needed, according to the interface you would would have the IP subnet binded to an… Read More »
Using OpenVPN Server on Linux as well as Windows machine, you may encounter this error trying to connect a client : Unable to obtain Session ID from “vpn.domain.tld”, port(s)=443: XML-RPC: TimeoutError Unable to obtain Session ID from “vpn.domain.tld”, port(s)=443: XML-RPC: ‘400’, ‘Bad Request’ This happen because HTTPS (SSL) port (TCP-443) is closed either on the… Read More »
Working in Active Directory Users and Computers (ADUC) trying to delete an Organizational Unit (OU), you get the following error : Active Directory Domain Services You do not have sufficient privileges to delete < Organizational Unit >, or this object is protected from accidental deletetion. By default, you need to uncheck the box “Protect object… Read More »
On a multi DC (Windows 2003 – 2008) Active Directory, you may encounter the following NTDS event : Active Directory failed to create an index for the following attribute. Attribute identifier: 591789 Attribute name: msFVE-RecoveryGuid A schema cache update will occur 5 minutes after the logging of this event and will attempt to create an… Read More »