Author name: alex

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)

Chrome Won’t Let You Proceed to Website with Invalid Certificate

As an IT professional it’s quite common that have to connect web servers with invalid certificates, for different reasons. For expample opening a management GUI of an appliance may be necessary to change its own certificate or TLS settings. Problem: sometimes chrome won’t let you open this website, and gives you no “Proceed on” button. …

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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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Devuan4/Debian11 usability annoyances

Problem: When pasting commandos to the shell, the shell no longer executes the command but shows the pasted text highlighted and shows the line feed but does not process it. Discussion: Devuan4 and Debian11 upgraded the readline library with a new default “feature” that should prevent noobs from accidentally pasting commands into the shell. But …

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Linux Connection NAT Helper not Working

Some protocols need more than one TCP or UDP connection. For NAT to work the firewall needs to open additional ports to allow client server connection automatically. Examples are FTP (port 21 handshake, additional ports for data), PPTP (port 1723 for handshake, proto GRE 47 for payload) Since Linux kernel (~) 4.7 these helpers are …

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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 systems 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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Cisco ASR-1001-X Update

There are at least two pieces of software you can update in a Cisco ASR-1001-X. The ROMMON (firmware) and the IOS itself. This router uses “Cisco IOS XE Software”. Which is an IOS process on a Linux kernel as far as I know. Cisco recommends specific ROMMON releases for different generations of software. You can …

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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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