Skip to main content

HTTP 502 Proxy Error While accessing Cisco ASDM

Are you getting the following error while accessing ASDM from your Client machine that is behind your corporate Firewal (TMG-2010)?
Unable to Launch ASDM from 172.16.1.1 (IP Address)
Unable to tunnel through proxy. Proxy returns “HTTP/1.1 502 Proxy Erro (Forefron TMG denied the specified Uniform Resource Locator (URL).”
So the actual restriction is in TMG 2010 and the connection is denied to the ASDM by TMG Default Rule, if your TMG Firewall is not configured to to access internal/external IP at which that ASA/PIX ASDM resides.
Suppose if your ASA/PIX firewall is on internal/inside network and in TMG you have created Web Access Rules so that it only allows connections from Internal to External Networks than connection from your Internal Clients to ASA/PIX can be denied by Default Web Access Rule of TMG 2010.
Either you can allow from Internal to Internal+External or You need to put exception in Allow Web access rule so that the connection from your internal networks is allowed.
Allowing all connections from internal to all internal and external networks is simpler, here I tell you how to put exceptions if your company doesn’t wants allow all connections.
For putting exception, you need to create a URL Set and Put it in allowed Exception Ruel.
Right Click Allow Web Access Rule > Properties > Select tab TO > Click ADD > Click URL Set > Click New
In the New URL Set Windows create the URL set as shown in the snap Below and give it any name, I Named it ASDM, when finished Click OK.
Once the URL Set is Created, Click Add Button to add this URL Set into the allowed destinations box.
Click OK and Apply the Changes in TMG and and Play with ASDM error Free.
Please mention if this worked for you..
Labels:

Comments

Post a Comment

Popular posts from this blog

How to import Putty Saved Connections to mRemoteNG

Just started using mRemoteNG and its being very cool to connect to different remote connection with different protocols e.g Window Remote Desktop, VNC to Linux, SSH, HTTP connection etc. from a single application. As new user I configured some remote desktop connection which was quite easy to figure out. But when I wanted to add SSH connections, it came in my mind to import all of the saved connections in the putty. But I couldn't figure it out how can it be done, though it was quite easy and here are the steps. Open your mRemoteNG Create a folder if you want segregation of multiple networks Create a new connection Enter the IP address of remote server under connection in Config pane Under the config pane, select protocol " SSH version 2 ".  Once you select protocol to SSH version 2 you are given option to import putty sessions, as shown in the snap below. In the above snap, I have imported CSR-AWS session from my saved sessions in Putty.
1 comment
Read more

SSL VPN vs IPSec VPN: Understanding the Key Differences

When it comes to securing communication over the internet, Virtual Private Networks (VPNs) are a cornerstone of modern networking. Two popular types of VPNs are SSL VPN and IPSec VPN . While both serve to encrypt and secure data, they differ significantly in terms of technology, use cases, and implementation. This blog post will help you understand these differences and choose the right solution for your needs. What is SSL VPN? An SSL VPN uses the Secure Sockets Layer (SSL) or its successor, Transport Layer Security (TLS) , to create a secure connection. It operates at the Application Layer (Layer 7) of the OSI model and is designed to provide secure access to specific resources over the internet. Key Features of SSL VPN: Ease of Use: Accessible via a standard web browser without the need for dedicated client software. Granular Access Control: Allows users to access specific applications or resources rather than the entire network. Port Usage: Uses TCP port 443, which is rarely...
Post a Comment
Read more

Authoritative DNS Servers Delegation and Internal DNS Explained

DNS (Domain Name System) plays a critical role in how users and systems find resources on the internet or within internal networks. Whether it's managing an internal domain in an enterprise or delegating parts of a domain for traffic distribution, DNS setups vary widely depending on needs. In this blog post, we’ll break down the different types of DNS setups, including authoritative DNS servers, DNS delegation, and how internal DNS functions within organizations. 1. Authoritative DNS Server An Authoritative DNS server is the final source of truth for a specific domain. When someone queries a domain (e.g., example.com ), the authoritative DNS server for that domain holds the DNS records (A records, CNAME, MX, etc.) and responds with the corresponding IP address. Key Points: Who can host it? Authoritative DNS servers are often hosted by domain registrars (e.g., GoDaddy, Namecheap) or cloud DNS providers (e.g., AWS Route 53, Cloudflare). However, organizations can also host their ...
Post a Comment
Read more