DNS failures when there are 2 wan
DNS failures when there are 2 wan
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Hello, I have relative knowledge of networks but there is something that I do not understand and if there is someone who understands why this happens, please help me and thank you in advance. I have 2 Wans from different providers and both are always connected but DNS 1.1.1.1 goes through the Wan. 1 and dns 8.8.8.8 goes through wan 2 and I don't understand why if the router mode is in backup and that shouldn't happen. When wan 2 fails, so does dns 8.8.8.8 and whoever uses that dns is offline
WAN1=200.8.16.1
WAN2=10.110.0.1
All of them should only go through the main wan, that is, wan2, but dns 8.8.8.8 does not do so.
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@Clive_A Exactly. This only happens with the DNS that are configured in the wan or those assigned to you by your provider. Said dns that is in the configuration of wan1, example: 8.8.8.8, this dns will not respond from the other wan2 in the event that wan1 is not available. It is like the DNS that is configured is blocked so that it only works with said wan but if wan 2 has 1.1.1.1 it will work correctly and you will be able to navigate correctly. The bakckup link works well, the problem lies in the DNS that is configured on the wan. My solution was to put a DNS that does not use my local network and that is enough
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Hi @Josvell
Thanks for posting in our business forum.
Josvell wrote
@Clive_A Exactly. This only happens with the DNS that are configured in the wan or those assigned to you by your provider. Said dns that is in the configuration of wan1, example: 8.8.8.8, this dns will not respond from the other wan2 in the event that wan1 is not available. It is like the DNS that is configured is blocked so that it only works with said wan but if wan 2 has 1.1.1.1 it will work correctly and you will be able to navigate correctly. The bakckup link works well, the problem lies in the DNS that is configured on the wan. My solution was to put a DNS that does not use my local network and that is enough
If I understand you right, you mean when the WAN1 fails over to WAN2, and WAN1 is using 8.8.8.8. After the failover and link backup, you switch to WAN2 which also uses 8.8.8.8, yet the 8.8.8.8 does not work anymore to resolve the DNS query. It seems to be disabled along with the load balancing and failover and the system thinks 8.8.8.8 is unusable.
Do I understand you correctly?
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@Clive_A Yes, exactly. If wan 1 has 8.8.8 8 and wan 2 has 1.1.1.1 in its configuration. If wan 1 stops having connectivity (internet) so will dns 8.8.8.8. If I maintain an infinite ping to youtube.com and another ping to 8.8.8.8 and cause the failure, both pings stop responding but after 15 seconds the ping from youtube.com responds again but 8.8.8.8 does not respond again and at the same time time Doing a traceroute to 8.8.8.8 shows how it tries to go through wan 1 even though the er605 knows it is down. NOTE: This happens when you cause it to have no connectivity (internet). Because if you cause the failure by physically disconnecting WAN 1, this failure never occurs. I apologize if there are any translation errors.
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Hi @Josvell
Thanks for posting in our business forum.
Josvell wrote
@Clive_A Yes, exactly. If wan 1 has 8.8.8 8 and wan 2 has 1.1.1.1 in its configuration. If wan 1 stops having connectivity (internet) so will dns 8.8.8.8. If I maintain an infinite ping to youtube.com and another ping to 8.8.8.8 and cause the failure, both pings stop responding but after 15 seconds the ping from youtube.com responds again but 8.8.8.8 does not respond again and at the same time time Doing a traceroute to 8.8.8.8 shows how it tries to go through wan 1 even though the er605 knows it is down. NOTE: This happens when you cause it to have no connectivity (internet). Because if you cause the failure by physically disconnecting WAN 1, this failure never occurs. I apologize if there are any translation errors.
Confirmed that this is a known issue. Dev is aware of this issue and will optimize this in future firmware updates.
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