Tag: juniper

  • How to capture text, backup configuration (Cisco,Juniper or anything)with Putty

    I dont think we need an introduction to the most widely used Remote console utility, PUTTY. Putty support SSH, Telnet, RLogin & RAW connections.

    If you telnet or SSH to your Cisco IOS routers or switches or Juniper Firewalls and ofcourse anything that support CLI and SSH or Telnet then one of the things you would prefer to do is to take a backup of the config (Running or Startup) or even capture session text including logs tech information etc. We discussed here about using Hypereterminal to capture text and hence backup and restore config on Cisco IOS Routers and Switches.

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  • How to fix Exchange & Outlook connection issues over IPSec VPN

    Recently we had this problem with this problem with an Exchange 2003 server in the HQ and Outlook Clients in a particular branch office. The Branch office connects into the HQ through a site to site IPSec VPN using Juniper Netscreen SSG20 firewalls on either end of tunnels.

    The Problem
    The Outlook clients would connect OK but suddenly loose connection to the Exchange server and never connect back. The Outlook Client status will say "Disconnected". The client PCs will however be able to ping the server and network connections look OK. This happened in random times and sometimes when sending large emails.

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  • How to enable Path MTU Discovery in Juniper Netscreen Firewalls (ScreenOS)

    If you have site to site IPSec VPNs configured between two network with your Juniper Netscreen or SSG firewalls and clients from one network access servers or services from the other network then it is advisable to enable Path MTU Discovery support on the Juniper firewalls.

    Juniper Netscreen or SSG firewalls running Screen OS by default disable the Path MTU Discovery support. This means, when an IP Packet with DF bit set ("1") in the ip Header and its size after IPSec Encapsulation is more the MTU of the Juniper VPN Firewall arrives at the VPN Firewall, the firewall will ignore the "DF" bit and simply fragments the packets and forwards it to the appropriate tunnel interface. This can cause serious problems with some applications. A classic example is the Microsoft Applications that rely on NetBIOS over TCP/IP which wouldn't prefer the packets being fragmented (and hence DF set).

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  • RANCID – Network Device Config Differ,Config Change alert,backup

    RANCID is Really Awesome New Cisco Config Differ. AS its name implies, RANCID monitors network device configuration, including software and hardware and uses CVS (Concurrent Version System) or Subversion to maintain history of changes. RANCID is simple and is easy to use.

    The same very functionality of RANCID can be used as a backup system for Network device config backup system or even a config change alert system as it can email changes from previous saved configurations. All this RANCID does by logging on to a network device using Telnet or SSH and runs various show commands to grab config changes (hardware & Software), send alert emails of any changes, format the info and commit to the CVS system.

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  • Ziptie – Opensource Network Inventory & Configuration Management Framework

    Ziptie is an Opensource Network Inventory and Configuration Management framework that can discover and manage network devices such as Routers,Switches and Firewalls. Ziptie out of the box support network devices from multiple major vendors. Ziptie is java based and is built on Eclipse framework. Ziptie can run on many Operating System platforms including Windows, Ubuntu, Fedora,Redhat, Madnriva amd most other Linux Distributions.

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  • Nipper – Network device Security Audit tool

    Nipper is an Opensource tool for network device congiguration and security audit. Nipper performs security audits of network device configuration files. The report produced by Nipper includes; detailed security-related issues with recommendations, a configuration report and various appendices. (more…)