Category Archives: Networking

Linux : OpenVPN client connection timeout after 24 hours

You probably experienced VPN session disconnection exactly 24 hours after you established the connection. Well, this is an expected behaviour since the OpenVPN Access Server implement a default 24 hours session timeout for user-locked and server-locked profiles. To workaround this limitation, you may set the timeout to a higher value using the following command : /usr/local/openvpn_as/scripts/sacli… Read More »

Cisco : Reset ASA OS to factory default

Here is a quick how to reset Cisco ASA (Adaptative Security Appliance) to factory default. You will need a serial console access to achieve this task. 1. At early boot process, just hit escape [esc] key when suggested as followed : Cisco Systems ROMMON Version (1.0(12)13) #0: Thu Aug 28 15:55:27 PDT 2008 Platform ASA5505… Read More »

IOS : Enable SSH and create user on Cisco Catalyst switch

Follow this quick tutorial to enable SSH access instead of Telnet and create a unprivileged user on Cisco IOS. 1. Enter in “Privilege EXEC” mode : enable 2. Enter in “Global Configuration” mode : conf t 3. Use the following commands to enable SSH, generate RSA keys and create the username/password : hostname <HOSTNAME> domain-name <FQDN.DOMAIN.TLD>… Read More »

JunOS : error: device ae0 not found

Having problem setting LACP interface on JunOS and got this “error: device ae0 not found” message? root@EX4200> show lacp interfaces ae0 error: device ae0 not found First, make sure the LACP interface members are properly configured : set interfaces ge-0/0/0 ether-options 802.3ad ae0 set interfaces ge-0/0/0 description “<OPTIONAL_DESCRIPTION>” set interfaces ge-0/0/1 ether-options 802.3ad ae0 set… Read More »

JunOS : Member’s information missing from provisioning database

The following error may occur importing an existing configuration from an EX virtual chassis member to another : re0: (vccpd): [member]: Member’s information missing from provisioning database re0: configuration check-out failed This is probably because you haven’t changed the device(s) serial numbers with the ones matching your new device. Edit the configuration file and replace… Read More »

JunOS : Interface ge-0/0/0.0 not enabled for switching

You may end up with the following error trying to create a LACP (802.3ad) bonded interface on your Juniper device : Error(s): ‘interface ge-0/0/0.0’ 1) Interface ge-0/0/41.0 not enabled for switching 2) configuration check-out failed This is probably due because you have a VLan interface set for these physical interfaces in your configuration such as… Read More »

JunOS : Can’t have mastership priority configuration with preprovisioned set

Getting this error committing the changes on a pre-provisioned EX switches virtual chassis? root@EX4200# commit synchronize [edit protocols] ‘bgp’ [edit virtual-chassis] ‘member 0’ Can’t have mastership priority configuration with preprovisioned set error: configuration check-out failed {master:0}[edit] root@EX4200# This mean you tried to set a mastership priority on a pre-provisioned configuration and this is not allowed.… Read More »

JunOS : How to upgrade from USB stick

There are several ways to update your JunOS software but one of the common and safe method is doing through the CLI and a USB memory stick. First, get your software from Juniper.net first and save it to a MSDOS formatted USB stick. Then, follow those steps (as root, through serial console is highly recommended)… Read More »

JunOS : Setting up DHCP forwarding

Here is how to configure DHCP forwarding across VLans on JunOS Juniper devices. set forwarding-options helpers bootp server <DHCP_SERVER_IP> set forwarding-options helpers bootp interface vlan.<VLAN_ID> Example : Assuming your DHCP server IP is “192.168.1.1” and the VLans you want DHCP forwarding enabled are “1” and “2” : set forwarding-options helpers bootp server 192.168.1.1 set forwarding-options… Read More »