Interface down on Cisco Nexus switch with “dcxNoACKi”

Problem: After an update of a server to Devuan4/Debian11the switch shuts down the interfaces to the server with status “dcxNoACKi” 48 minutes after the reboot. Discussion: the switch is a Cisco Nexus 5000 switch. It implements “Data Center Bridging Capability Exchange (DCBX)”. The server is a Dell server with X710 Controller 10GbE with i40e drivers. …

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Devuan Update Fails with Signature Invalid

Problem: (5. September 2022) when fetching Devuan updates you get the following error: Discussion: The devuan key to sign the repository list has expired on 3. September 2022. This is an embarrassing fail from Devuan. But the solution is quite simple Solution: Install the new keyring manually: Version: tested with Devuan 3 (beowulf), Devuan4 (chimaera)

Smartd Reports “Reallocated_Sector_Ct” erroneously

Problem: In syslog you find a line like this: But when you check with “smartctl -a” you find a reallocated sector count of zero: Discussion: The harddisk had actually no reallocated sectors, but Smartctrl (Smartmontools) reported a wrong error, because when it was started a different harddisk with errors was found as /dev/sda, but with …

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Debian Curl/PHP/wget etc show an certificate error falsely

Problem: curl php wget and others show a cert error like the following since 6. Oct 2021, even though the cert has not expired: The asked server uses a Letsencrypt certificate. Discussion: Currently Letsencrypt includes two chains for validation of the certificate: Cert -> R3 -> ISRG Root X1 (in new trust store) Cert -> …

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Devuan / Debian Versions

Admins who prefer a Unix style operation system and don’t like the centralized “one tool doing it all” approach of systemd, switch to Devuan. This mostly improves uptime over boot time. Admins of servers don’t care about boot time and prefer uptime. This list keeps track of the related versions of Devuan and Debian. Debian …

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DHCP Relay on Linux

DHCP relaying is used to forward DHCP requests to a DHCP server if the client and the server are not on the same network. One standard implementation of this is isc-dhcp-relay which is part of the isc-dhcp package. Problem: The dhcrelay is forwarding the dhcp request to the dhcp server and the dhcp server is …

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