EFA 2.4.5 DNS is not resolving FQDN

Alberto_Oter — Tue, 27 Sep 2022 17:03:03 GMT

Hi experts,

Can someone tell if the EFA needs some extra configuration to force the FQDN resolution (nslookup) from a remote DNS?

Here some highlights of the scenario

-I'm trying to add a new entry to efa notification subscribers list, no other subscriber exist currently.

-In my command instead of the address I'm trying to configure FQDN, trying that I'm getting an error:

Command: (efa:extreme)hostname#efa notification subscribers add-syslog-relp --address hostname01-.eng.phone.net --cacert hostname01-ca-combined.pem

Output: Error : Error on registration for a 'relp' handler on endpoint 'hostname01-.eng.phone.net:514'. ERROR: The host from the endpoint URL is not reachable.

-I currently have IP reachability from EFA external Network to the remote DNS server. (ping/tracepath, both works properly).

-If I try to execute a nslookup with the FQDN hostname01-.eng.phone.net I'm getting the following:

;; connection timed out; no servers could be reached

-I add the following inputs if needed:

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
# 127.0.0.53 is the systemd-resolved stub resolver.
# run "systemd-resolve --status" to see details about the actual nameservers.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

systemd-resolve --status
Failed to get global data: Unit dbus-org.freedesktop.resolve1.service not found.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Thanks in advance

Re: EFA 2.4.5 DNS is not resolving FQDN

Michael_Morey — Thu, 12 Oct 2023 14:37:13 GMT

Correcting my earlier response with new process in latest EFA/XCO as it is not recommended to manually edit the resolv.conf file:

To correctly configure DNS on the TPVM issue the following commands in SLXOS:
** Configuring DNS on the TPVM will cause issues with K3s and cause nodes to show Down **

POD2-Spine2# conf
Entering configuration mode terminal
POD2-Spine2(config)# tpvm
POD2-Spine2(config-tpvm-TPVM)# dns primary-server 8.8.8.8
POD2-Spine2(config-tpvm-TPVM)# dns secondary-server 8.4.4.8

Next issue the following command from the active Node TPVM:

sudo /apps/efa/./update-dns.sh --dns-action allow

Once DNS information is forwarded to the pods allow some time for the nodes to restore (Active UP/Standby UP)

topic EFA 2.4.5 DNS is not resolving FQDN in Data Center (SLX)

EFA 2.4.5 DNS is not resolving FQDN

Re: EFA 2.4.5 DNS is not resolving FQDN