# No ploop support in the kernel, or kernel is way too old. - CentOS 5.11



## ICPH (Nov 6, 2014)

Hi, can u please advice me how to enable ploop on CentOS OpenVZ dedi server, if its good idea?

 

vzctl returns (in /var/log/vzctl*):



```
No ploop support in the kernel, or kernel is way too old.
Make sure you have OpenVZ kernel 042stab058.7 or later running,and kernel ploop modules loaded.
```

 

uname -r



```
2.6.18-398.el5.028stab116.1
```

 

cat /etc/red*



```
CentOS release 5.11 (Final)
```

 

from /etc/grub.conf



```
title OpenVZ (2.6.18-398.el5.028stab116.1)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-398.el5.028stab116.1 ro root=/dev/vg/root selinux=0
        initrd /initrd-2.6.18-398.el5.028stab116.1.img
```

 

when tried yum install ploop:



```
ploop-lib-1.12.1-1.x86_64 from openvz-utils has depsolving problems
  --> ploop-lib conflicts with ovzkernel
```

 

yum upgrade,update is all up to date..

 

My previous openvz server was CentOS 5 too (i guess another version) and ploop worked (im not sure if it was ploop)

 

Please can i anyhow upgrade kernel or such to support ploop? (without big downtime)

 

 

 

---

Here is how to upgrade to openvz kernel that ploop wants: https://openvz.org/028_to_042_kernel_upgrade But im afraid of that ext4 update, looks quite difficult all

 

 

PS:

here is how to get rid of errors creating VMs:

 

Edit /etc/vz/vz.conf
change: 
VE_LAYOUT=ploop
to:
VE_LAYOUT=simfs


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## rds100 (Nov 6, 2014)

Install CentOS 6.


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## ICPH (Nov 6, 2014)

Without installing version 6. i said no big downtime way


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## rds100 (Nov 6, 2014)

Maybe it's possible to install and use the el6 based kernel while still using the CentOS 5 userland, but i'm not sure about that. You will have to try it on a test box first.


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## AshleyUK (Nov 6, 2014)

Do you still have access to your old OpenVZ server to set what Kernel you had running?


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## Francisco (Nov 6, 2014)

rds100 said:


> Maybe it's possible to install and use the el6 based kernel while still using the CentOS 5 userland, but i'm not sure about that. You will have to try it on a test box first.


It is.

It's not super pretty as you get some sysfs quirks, but for the most part it works. The OP loses out on the improvements ext4 brings on, but being stuck on 2.6.18 suuuucks.

Francisco


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## Geek (Nov 6, 2014)

If I recall correctly there's never been any Ploop device support in 2.6.18, nor will it work at all under an ext3-fs.  I ran through the ext4 conversion in Dev a couple of times without problems.  Do you have a testing environment?


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## Geek (Nov 6, 2014)

Francisco said:


> It is.
> 
> 
> It's not super pretty as you get some sysfs quirks, but for the most part it works. The OP loses out on the improvements ext4 brings on, but being stuck on 2.6.18 suuuucks.
> ...



Yeah, a quirky config like that seems too risky, IMO... seems like it's an invitation for bugs and package conflicts...


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## Francisco (Nov 6, 2014)

Geek said:


> Yeah, a quirky config like that seems too risky, IMO... seems like it's an invitation for bugs and package conflicts...


We used to run it some but we had a lot of softlocks. In the end we weren't sure if the softlocks were because of vswap being completely broken or if it was conflicts with .18, glibc, etc.

Francisco


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## Geek (Nov 6, 2014)

Francisco said:


> We used to run it some but we had a lot of softlocks. In the end we weren't sure if the softlocks were because of vswap being completely broken or if it was conflicts with .18, glibc, etc.
> 
> 
> Francisco


Crap that had to be hard to tell one way or the other. Must have been in the earlier days of vswap, like within the first year or so? Vswap was pretty wonky up until ... hmm, around 068.8 or so.


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