# Odd Firewall Behavior

**URL:** <https://forums.suse.com/t/odd-firewall-behavior/25089>\
**Category:** Chatting over the Back Fence\
**Created:** [February 6, 2014, 8:29pm UTC](https://forums.suse.com/t/odd-firewall-behavior/25089 "2014-02-06T20:29:45Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![System1](https://avatars.discourse-cdn.com/v4/letter/s/51bf81/32.png) [@System1](https://forums.suse.com/u/System1)\
**Post date:** [February 6, 2014, 8:29pm UTC](https://forums.suse.com/t/odd-firewall-behavior/25089/1 "2014-02-06T20:29:45Z")

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I have an ISP link that goes into a 5 port fast ethernet switch.  
Off of that switch are hanging two firewalls. One with IP (fakes)  
Firewall A 222.222.222.1 the other Firewall B 222.222.222.2.  
Coming across Firewall B is a VPN that supports connections to SERVER1.  
SERVER1’s default gateway is set to Firewall B.

When Firewall A is plugged into the switch, traffic to SERVER1 becomes  
inordinately slow or stops altogher. When Firewallo A is removed from the  
switch, traffic returns to normal.

WTH?

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**Author:** ![system](https://us1.discourse-cdn.com/flex022/uploads/suse/original/2X/5/5012ba89e3ffb5220dac47d5ea0ba032e2fe1cb6.png) [@system](https://forums.suse.com/u/system)\
**Post date:** [February 6, 2014, 8:31pm UTC](https://forums.suse.com/t/odd-firewall-behavior/25089/2 "2014-02-06T20:31:02Z")

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GofBorg wrote:  
[color=blue]

> I have an ISP link that goes into a 5 port fast ethernet switch.  
> Off of that switch are hanging two firewalls. One with IP (fakes)  
> Firewall A 222.222.222.1 the other Firewall B 222.222.222.2.  
> Coming across Firewall B is a VPN that supports connections to SERVER1.  
> SERVER1’s default gateway is set to Firewall B.
> 
> When Firewall A is plugged into the switch, traffic to SERVER1 becomes  
> inordinately slow or stops altogher. When Firewallo A is removed from the  
> switch, traffic returns to normal.
> 
> WTH?[/color]

I have tested for bad cabling.

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**Author:** ![system](https://us1.discourse-cdn.com/flex022/uploads/suse/original/2X/5/5012ba89e3ffb5220dac47d5ea0ba032e2fe1cb6.png) [@system](https://forums.suse.com/u/system)\
**Post date:** [February 6, 2014, 8:31pm UTC](https://forums.suse.com/t/odd-firewall-behavior/25089/3 "2014-02-06T20:31:16Z")

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GofBorg wrote:  
[color=blue]

> I have an ISP link that goes into a 5 port fast ethernet switch.  
> Off of that switch are hanging two firewalls. One with IP (fakes)  
> Firewall A 222.222.222.1 the other Firewall B 222.222.222.2.  
> Coming across Firewall B is a VPN that supports connections to SERVER1.  
> SERVER1’s default gateway is set to Firewall B.
> 
> When Firewall A is plugged into the switch, traffic to SERVER1 becomes  
> inordinately slow or stops altogher. When Firewallo A is removed from the  
> switch, traffic returns to normal.
> 
> WTH?[/color]

Oh and bad switch port.

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex022/uploads/suse/original/2X/5/5012ba89e3ffb5220dac47d5ea0ba032e2fe1cb6.png) [@system](https://forums.suse.com/u/system)\
**Post date:** [February 6, 2014, 10:32pm UTC](https://forums.suse.com/t/odd-firewall-behavior/25089/4 "2014-02-06T22:32:07Z")

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GofBorg sounds like they ‘said’:  
[color=blue]

> WTH?[/color]

So my response to GofBorg’s comment is…

Check for any weird routing loops or anything like that?

–  
Stevo