Hello,

My server _seem_ to have problem with new kernel after updated by up2date. I kept a lot of old kernel, is it safe to use old kernel? I mean if I reboot with old kernel, any chance my server won't boot at all?

Current kernel is 2.4.21-15
Old kernel is 2.4.21-3

It will boot, but it won't be secure. I would think fixing the issues with the new kernel is more important.

What problems are you getting ? Did you read the boot log for what error messages there is? or get the data center to interactively boot it up so that they can detect the issue?

well you need to go to 2.4.25

He's on RHE based on those kernel versions. Basically RHE kernels are a lot better than the stock kernels since they backported 2.6 series improvements to a more stable platform. So he should still try and get it to work.

Originally posted by Boost
well you need to go to 2.4.25

NEGATIVE! 2.4.26 is the newest with no known vulns. But hes on rhe. Anyways its never good to run a outdated kernels, your asking for a root compromise.

not safe at all

I don't know, my server iowait go sky high at random time, right now there is only 40 visitors on the forums, but the top stat and free stat are as follow:

17:43:53 up 2 days, 9:37, 1 user, load average: 20.99, 9.59, 4.06
222 processes: 219 sleeping, 3 running, 0 zombie, 0 stopped
CPU states: cpu user nice system irq softirq iowait idle
total 3.3% 0.0% 0.5% 0.7% 0.0% 95.2% 0.0%
Mem: 505416k av, 499776k used, 5640k free, 0k shrd, 3348k buff
374316k actv, 70240k in_d, 6704k in_c
Swap: 522104k av, 299048k used, 223056k free 213736k cached

PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME CPU COMMAND
4024 mysql 15 0 136M 44M 1872 S 1.9 9.0 90:15 0 mysqld
3096 apache 15 0 5332 4216 2720 D 0.3 0.8 0:00 0 httpd
4062 root 15 0 2596 1328 944 S 0.1 0.2 0:01 0 ipalert_statd
512 apache 15 0 10084 5484 2968 D 0.1 1.0 0:18 0 httpd
521 apache 15 0 10392 5020 2576 R 0.1 0.9 0:19 0 httpd
3068 apache 16 0 6272 5088 3124 S 0.1 1.0 0:00 0 httpd
3076 apache 15 0 5220 4044 2280 S 0.1 0.8 0:00 0 httpd
3102 fiji 15 0 1372 1372 904 R 0.1 0.2 0:00 0 top
3218 apache 15 0 4976 3832 2780 D 0.1 0.7 0:00 0 httpd
3219 apache 15 0 5692 4628 3216 S 0.1 0.9 0:00 0 httpd
1 root 15 0 508 472 448 S 0.0 0.0 0:03 0 init
2 root 15 0 0 0 0 SW 0.0 0.0 0:00 0 keventd
3 root 15 0 0 0 0 SW 0.0 0.0 0:00 0 kapmd
4 root 34 19 0 0 0 SWN 0.0 0.0 0:00 0 ksoftirqd/0
7 root 25 0 0 0 0 SW 0.0 0.0 0:00 0 bdflush
fr-bash-2.05b$ free
total used free shared buffers cached
Mem: 505416 500124 5292 0 3400 212248
-/+ buffers/cache: 284476 220940
Swap: 522104 297916 224188
-bash-2.05b$


Some one here tell me that the kernel of RHE have some problem with iowait, and my server just behave like this several weeks ago. Before that, everything work fine... so I want to try to use old kernel...

add this to the rc.local

echo 100 > /proc/sys/vm/inactive_clean_percent
echo 2 10 20 > /proc/sys/vm/pagecache

up2date -f kernel

and reboot

Originally posted by sprintserve
He's on RHE based on those kernel versions. Basically RHE kernels are a lot better than the stock kernels since they backported 2.6 series improvements to a more stable platform. So he should still try and get it to work.

Does it applies for Fedora's kernels too ?

No. It doesn't.

Originally posted by thelinuxguy
add this to the rc.local

echo 100 > /proc/sys/vm/inactive_clean_percent
echo 2 10 20 > /proc/sys/vm/pagecache

up2date -f kernel

and reboot

what do these lines do?

An added note is that however the new Fedora Core 2 comes with 2.6 kernel. So there wouldn't be a need to backport the improvements anyway.

I strongly suggest against an old kernel. I reecently forgot to update a linux machine i had at home running a old fedora kernel and it was hacked with the zkmem. I strongly suggest updateing them with in afew days they come out.

What's the problem FrzzMan is having exactly?
Could someone give an explanation of this issue?
I was updating my kernel too but I would like to know if it could cause some problems to my server before updating.

Is it safe to put an old tire on your car.

Originally posted by thelinuxguy
add this to the rc.local

echo 100 > /proc/sys/vm/inactive_clean_percent
echo 2 10 20 > /proc/sys/vm/pagecache

up2date -f kernel

and reboot

fixes the kernel issues with rhe is most cases