A magical internet connection.



  • Each of our clients' laptops require a few configuration changes to work outside the network compared to inside the network. The main one is the proxy only works while inside the network (meaning in a site that actually has IT backbone) and no use can reach it while remote since it has a non-routeable address (I forget the official term, sorry). Then while remote to access internal services (like email and shared drives) they connect to the VPN which is actually a special webpage that interfaces with software already installed on their system to create the VPN tunnel, they need internet access to reach this page. This was my understanding of the system before a special caller who appears to have quite a magical internet connection.



    Call starts off mundanely with the oft used phrase "my internet doesn't work", but she can access email (which I presumed she meant cached versions), but can't access web pages or shared drives. So I started out with checking her IP, standard "assigned by DHCP" setup, IP 192.168.123.104 (Odd number for the third octet, but whatever) netmask 255.255.255.0 gateway: 192.168.3.3 (Yes, the third octet is different from the IP's). Alright, so she got a shitty lease, except I find out at this point she can in fact reach the VPN page, is connected and can transmit emails. I do ping and traceroute checks anyways, they fail with destination host unreachable, traceroute notably failing on the first hop. Just out of curiosity I ask her for her proxy settings, normal for someone who in the network, so I ask her to disable the proxy and she can reach the internal portal! Yay! But not google, BBC or anything outside the network...



    So that leaves us with this: She is able to access the external VPN site despite her not being able to reach her gateway, being on a completely different network from where the proxy is and is able to send/receive emails.


  • Garbage Person

     Where I'm from, this crap means they're lying to you.



  •  No, it all sounds reasonable. If she has a proxy set, and can reach that proxy on the local subnet, then many things will work - You will be able to reach the proxy, and the proxy will be able to connect to most things. This won't work with ping, as the gateway is unreachable, or anything else that isn't http. https might be out too, and vpn is right out.

    Drop the proxy, and you can reach anything on 192.168.123.x, but nothing else.

    Sounds right to me. They just need to get their dhcp set to give a valid gateway address.



  • @robbak said:

     No, it all sounds reasonable. If she has a proxy set, and can reach that proxy on the local subnet, then many things will work - You will be able to reach the proxy, and the proxy will be able to connect to most things. This won't work with ping, as the gateway is unreachable, or anything else that isn't http. https might be out too, and vpn is right out.

    Drop the proxy, and you can reach anything on 192.168.123.x, but nothing else.

    Sounds right to me. They just need to get their dhcp set to give a valid gateway address.

    That would be true if the addresses she can reach weren't on the same subnet as the proxy, which isn't the subnet she's on.



  • @Lingerance said:

    @robbak said:

     No, it all sounds reasonable. If she has a proxy set, and can reach that proxy on the local subnet, then many things will work - You will be able to reach the proxy, and the proxy will be able to connect to most things. This won't work with ping, as the gateway is unreachable, or anything else that isn't http. https might be out too, and vpn is right out.

    Drop the proxy, and you can reach anything on 192.168.123.x, but nothing else.

    Sounds right to me. They just need to get their dhcp set to give a valid gateway address.

    That would be true if the addresses she can reach weren't on the same subnet as the proxy, which isn't the subnet she's on.

    I'd have a go at manually setting the netmask to 255.255.0.0, you never know.  Could be a misconfigured router, and 192.198 is a /16 after all.

    Actually, maybe the first thing to try would be "ipconfig /renew"?  Could it be a stale old lease from some dodgy home router that gives out indefinite leases?


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