DNS failures on regular basis

sh_man

Sorry - forgot to mention its i386

jimp

If you have multi-wan, you really do need to specify at least one DNS server for each gateway under System > General, unless they're dynamic and get their DNS servers over PPPoE/DHCP - still, specifying them manually is better.

Two DNS servers for each WAN is best.

sh_man

Have two DNS per WAN but am still getting issues.

The DNS appears to disappear for 5 minutes then comes back. Very odd

jimp

Are you maxing out your state table, perhaps?

Seems unusual that just DNS would stop, and nothing else.

sh_man

Don't think so.

Have been clutching at straws and I think it is the DNS that our temporary internet supplier has given us.

Changing the DNS to the OpenDNS servers seems to have given us a stable system for the last couple of hours.

Will see what happens when the 100 users hit it in an hour when their program finishes and they all walk in with their iPhones :)

jimp

You could use OpenDNS and Google DNS (8.8.8.8 / 8.8.4.4), one from each on WAN/WAN2, might be even more stable.

robfantini

I just ran into a similar issue.

After reading that I should add DNS i/p addresses to my 2-nd WAN , i was not able to access the webgui, or ping google.com from the console.

We have multi-lan .

I will restore an earlier config and reboot.

here are parts of the config:


# good:

                <dns1gwint>wan</dns1gwint>                                                             
                <dns2gwint>wan</dns2gwint>                                                             
                <dns3gwint>none</dns3gwint>                                                            
                <dns4gwint>none</dns4gwint>                                                            
                <dnsserver>8.8.8.8</dnsserver>                                                         
                <dnsserver>75.75.75.75</dnsserver>                                                     
                <dnsserver>8.8.4.4</dnsserver>                                                         
                <dnsallowoverride><maximumstates><maximumtableentries><reflectiontimeout>#bad
                        <branch><dns1gwint>wan</dns1gwint>                                                             
                <dns2gwint>wan</dns2gwint>                                                             
                <dns3gwint>opt1</dns3gwint>                                                            
                <dns4gwint>opt1</dns4gwint>                                                            
                <maximumstates><maximumtableentries><reflectiontimeout><dnsserver>8.8.8.8</dnsserver>                                                         
                <dnsserver>8.8.4.4</dnsserver>                                                         
                <dnsserver>8.8.8.8</dnsserver>                                                         
                <dnsserver>8.8.4.4</dnsserver>                                                         
                <dnsallowoverride></dnsallowoverride></reflectiontimeout></maximumtableentries></maximumstates></branch></reflectiontimeout></maximumtableentries></maximumstates></dnsallowoverride>

robfantini

so after restart I gould oing:


Enter a host name or IP address: google.com

PING google.com (74.125.113.106): 56 data bytes
64 bytes from 74.125.113.106: icmp_seq=0 ttl=53 time=34.514 ms
64 bytes from 74.125.113.106: icmp_seq=1 ttl=53 time=33.338 ms
64 bytes from 74.125.113.106: icmp_seq=2 ttl=53 time=34.110 ms

--- google.com ping statistics ---
3 packets transmitted, 3 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 33.338/33.987/34.514/0.488 ms

Press ENTER to continue.

jimp

You can't have the same IP on both WANs. Having conflicting routes probably freaked something out.

This would work:
8.8.8.8 WAN
8.8.4.4 OPT1
208.67.222.222 WAN
208.67.220.220 OPT1

robfantini

OK, that fixed it for us. thanks.