Uh-oh. I Guess Now I Gotta Upgrade

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OldStrummer
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Uh-oh. I Guess Now I Gotta Upgrade

Post by OldStrummer » 2020/06/20 23:40:52

I think I had an account here a few years ago, when I first installed CentOS 6.5, but I can't find any record of it, so consider me new.

I'm a Linux (and Mac) guy in a sea of Windows users. I work for a software company, and somehow managed to get them to spring for a server, which has become pretty much my personal sandbox. No complaints, and it's been a real boon. And from my standpoint, 6.x has been virtually bulletproof over the years. Since there wasn't an ugrade path from 6.x to 7, I decided to stick with what was working for me. Alas, 6 is dying soon, and 8 is now on the streets.

So, I'm realizing a fresh install is due. Here's where it gets sticky: I have very little physical access to the machine, especially in this day of COVID-19. I do most of my work remotely. I installed XRDP which works nicely (although it burps on occasion). So, I'm wondering if it's possible to download the ISO image of 8.2, mount it, and somehow install from there. I just don't know how I'd get it to be the boot device so that I can lay down the new OS.

Am I asking the impossible? The computer is a Dell T420, which was turned on its side and placed in a rack. I don't even remember if it has an optical drive. If I can't do a remote install, I will have to make a bootable USB drive, go to the office, and connect a keyboard and monitor to do the install.

Any suggestions?

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TrevorH
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by TrevorH » 2020/06/21 00:21:15

A T420 is a Dell Poweredge server and those often come with an iDRAC. If you have the right license for it then that has a built-in remote console that's just like standing in front of the server. That would also have the ability to mount iso imagesin a virtual DVD drive that the server can boot from.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

OldStrummer
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by OldStrummer » 2020/06/23 01:39:31

TrevorH wrote:
2020/06/21 00:21:15
A T420 is a Dell Poweredge server and those often come with an iDRAC. If you have the right license for it then that has a built-in remote console that's just like standing in front of the server. That would also have the ability to mount iso imagesin a virtual DVD drive that the server can boot from.
It's been years since we purchased the PowerEdge, so I don't recall licensing iDRAC. I don't think we were forward-thinking enough for that. :)

I suspect i'm going to find myself on my hands and knees for a bit. I'd better make sure I have on a tough pair of jeans.

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TrevorH
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by TrevorH » 2020/06/23 08:24:20

IT's quite possible that you have an iDRAC chip in the machine but that it's not got the correct license to allow a remote console to be used. You can only check the inventory online at support.euro.dell.com and entering the machine serial number. You can get that from the output of the dmidecode command.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

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jlehtone
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by jlehtone » 2020/06/23 12:49:45

Functional remote management infra is awesome (or the grass just seems greener over that fence).
OldStrummer wrote:
2020/06/23 01:39:31
I don't think we were forward-thinking enough for that. :)
At least you didn't pay for the license then. Think of a machine that has the chip, has the license, has perhaps even network cable to the port that the chip uses, but the chip was never ("we won't need", "no time for that now") configured properly, so it does not listen. :oops:

On the "bright side", at least recent Firefox on CentOS refuses to talk to old version of iDRAC, can't open console on browser, etc. You were saved from those "almost there" moments.

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TrevorH
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by TrevorH » 2020/06/23 13:06:03

How old an iDRAC are we talking there?
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

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jlehtone
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by jlehtone » 2020/06/23 21:57:47

About 9 years, and firmware possibly not the latest.

OldStrummer
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by OldStrummer » 2020/07/01 20:24:29

Thanks for the replies so far. Here's an update:

I went into the office today, and got to work on prepping the machine. I attached a 1TB exFAT USB HDD and backed up the vital files (technically, nothing is irreplaceable, but if I don't have to re-download, re-install...). I then created a bootable USB stick with CentOS 8.2 and successfully booted into it. I didn't do the actual install yet, because there are a couple of things I want to pursue first:

I pulled the cover off the machine and determined that it has four 8GB memory sticks, two per bank of slots (there are a total of twelve). My research shows this is likely DDR3-1600 1.35v RDIMM (I've sent a message to the memory vendor asking for the correct numbers). For a measly $70 or so, I can double the amount of RAM, which is something I need as well.

I also found that I have the option to boot from BIOS or UEFI. It's currently set to BIOS (which is how I booted into the USB stick), but I can make a UEFI boot drive just as well. My understanding is UEFI is "modern" and BIOS is "ancient." So, unless there's a reason not to, I place to experiment with setting UEFI as the boot mode and see how it goes. Any ideas on this? It shouldn't matter to CentOS I would think, but I could be wrong. So, trying to save time...

So, I'm just about ready. I may go ahead and install the OS instead of waiting for the memory, but I'd like to be able to get everything done so I can wrap it up, put it back on the rack and get to work configuring it with the stuff I need.

UEFI or BIOS?

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jlehtone
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by jlehtone » 2020/07/01 21:08:35

I prefer UEFI, not that it would make a huge difference on such server.
OldStrummer wrote:
2020/07/01 20:24:29
I pulled the cover off the machine and determined that it has four 8GB memory sticks, two per bank of slots (there are a total of twelve). My research shows this is likely DDR3-1600 1.35v RDIMM (I've sent a message to the memory vendor asking for the correct numbers). For a measly $70 or so, I can double the amount of RAM, which is something I need as well.
T420 seems to have had E5-2400 or E5-2400v2 family processors. Max two of them. Those processors had three memory channels.

Since you have two modules in each bank (of six), you must have two CPUs on the board. There is one bank for each CPU.
You have two modules per CPU, so only 2 out of 3 memory channels are in use.

If you double the modules (to eight), then you will have one module in each of two channels, and the third channel will have two modules. Possible, but perhaps not optimal. If the modules are really so cheap, then I would go to full 12.

PS. You can probably read data about the memory models with:

Code: Select all

sudo dmidecode

OldStrummer
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Re: Uh-oh. I Guess Now I Gotta Upgrade

Post by OldStrummer » 2020/07/01 21:57:26

jlehtone wrote:
2020/07/01 21:08:35
I prefer UEFI, not that it would make a huge difference on such server.
It's an option. I know it's an old machine, but I'd like to keep it limping along for a while (I'm working with HQ to get a brand new box, but if this is still serviceable, why not?).

Code: Select all

sudo dmidecode
Wow! That dumps a lot of data! I think it has what I need to go forward with adding memory.

THANKS!

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