similar to: Anyway to ensure SSH availability?

Displaying 20 results from an estimated 3000 matches similar to: "Anyway to ensure SSH availability?"

2010 Sep 10
5
Traffic shaping on CentOS
I've been trying to do traffic shaping on one of my public servers and after reading up, it seems like the way to do so is via tc/htb. However, most of the documentation seems at least half a decade old with nothing new recently. Furthermore, trying to get documentation on tc filters turned up a blank. man tc refers to a tc-filters (8) but trying to man that gives a no such page/section
2010 Jul 10
4
Redundant LAN routing possible?
I've been reading that it's possible to set up a system with multiple NIC to provide redundant internet connectivity such that it will switch to a secondary connection if the primary ISP fails. Is it possible in a similar way to setup redundant LAN routing? I read that it is possible to aggregate/bond multiple NIC to stackable switches that support link aggregation and redundancy. But if
2011 Jun 08
3
High system load but low cpu usage
I'm trying to figure out what's causing an average system load of 3+ to 5+ on an Intel quad core. The server has with 2 KVM guests (assigned 1 core and 2 cores) that's lightly loaded (0.1~0.4) each. Both guest/host are running 64bit CentOS 5.6 Originally I suspected maybe it's i/o but on checking, there is very little i/o wait % as well. Plenty of free disk space available on all
2011 Jun 29
3
yum update -> [Errno 4] Socket Error: timed out
Trying to update a second CentOS box, I'm getting this error repeatedly: [Errno 4] Socket Error: timed out I'm getting this on every mirror and have gone through the list of mirrors more than a dozen times. Oddly, the RPMs I'm trying to upgrade I upgraded just yesterday without a problem on another machine on the same LAN with no problems whatsoever. I can ping mirrors fine. There
2011 Jun 09
4
Possible to use multiple disk to bypass I/O wait?
I'm trying to resolve an I/O problem on a CentOS 5.6 server. The process basically scans through Maildirs, checking for space usage and quota. Because there are hundred odd user folders and several 10s of thousands of small files, this sends the I/O wait % way high. The server hits a very high load level and stops responding to other requests until the crawl is done. I am wondering if I add
2011 Jun 23
4
Jumbo frames problem with Realtek NICs?
I was trying to do some performance testing between using iSCSI on the host as a diskfile to a guest vs the VM guest using the iSCSI device directly. However, in the process of trying to establish a baseline performance figure, I started increasing the MTU settings on the PCI-express NICs with RTL8168B chips. First bottleneck was discovering the max MTU allowed on these is 7K instead of 9K but
2012 Aug 03
4
Urgent help on replacing /var
In a moment of epic stupidity, having ran out of space on the root partition of a server due to /var chewing up the space, I added a separate drive for the purpose of mounting it as /var To do so, I mounted the new drive as /var2, cp -R (in hindsight should had rsync to preserve attributes), deleted the original /var to free up space, edited fstab and rebooted... unsurprisingly to a fubar'd
2016 Mar 01
10
Any experiences with newer WD Red drives?
Might be slightly OT as it isn't necessarily a CentOS related issue. I've been using WD Reds as mdraid components which worked pretty well for non-IOPS intensive workloads. However, the latest C7 server I built, ran into problems with them on on a Intel C236 board (SuperMicro X11SSH) with tons of "ata bus error write fpdma queued". Googling on it threw up old suggestions to
2010 Jun 28
3
CentOS MD RAID 1 on Openfiler iSCSI
Has anybody tried or knows if it is possible to create a MD RAID1 device using networked iSCSI devices like those created using OpenFiler? The idea I'm thinking of here is to use two OpenFiler servers with physical drives in RAID 1, to create iSCSI virtual devices and run CentOS guest VMs off the MD RAID 1 device. Since theoretically, this setup would survive both a single physical drive
2012 Apr 04
2
Installing CentOS 6.2 *TO* a USB drive, not installing from USB.
I'm trying to setup a very small system intended for doing monitoring/logging. It's done on an Intel Atoms in a small box and the idea was to simply run it off a pair of USB flash drives in software RAID 1. Now the problem is that while the 6.2 DVD installer could go through the entire install process, grub will load then just stop at the prompt. The system will work if I use a SATA hard
2010 Jul 03
4
ESXi, KVM or Xen?
Which of these would be the recommended virtualization platform for mainly CentOS guest on CentOS host for running a virtualized mail server? From what I've read, objectively it seems that VMWare's still the way to go although I would had like to go with Xen or KVM just as a matter of subjective preference. VMWare's offering seems to have the best support and tools, plus likely the
2011 Jun 25
3
Jumbo Frame performance or lackof?
After successfully getting higher MTU to work on my Realtek NICs, I started testing the impact of higher MTU on file transfers using NFS exported ramdisk to ramdisk. The results were unexpected. The higher the MTU on the sending NIC, the lower the file transfer speed. I tested by using time cp to copy a 1GB file (In case compression might affect the results, so I dd the test file from the CentOS
2011 Mar 21
4
mdraid on top of mdraid
Is it possible or will there be any problems with using mdraid on top of mdraid? specifically say mdraid 1/5 on top of mdraid multipath. e.g. 4 storage machines exporting iSCSI targets via two different physical network switches then use multipath to create md block devices then use mdraid on these md block devices The purpose being the storage array surviving a physical network switch
2009 Oct 06
3
how to turn off "update info" on /var/log/messages
we have CENTOS 5.3 on DELL server. This server is inside firewall and it continue get error messages on /var/log/messages: error getting update info: Cannot retrieve repository metadata (repomd.xml) for repository: base. Please verify its path and try again anyone know how to turn off it? Thanks. ___________________________________________________ ??????? ? ????????????????
2005 Oct 19
3
Duplicated packages after yum crash
Hi, I asked yum to update all packages on my CentOS 4.1 system and glibc was among them. Yum crashed in the middle and now I've some packages installed twice: 2 zlib-1.2.1.2-1.2 2 ncurses-5.4-13 2 mysql-4.1.10a-2.RHEL4.1 2 libstdc++-3.4.4-2 2 libstdc++-3.4.3-22.1 2 libselinux-1.19.1-7 2 libgcc-3.4.4-2 2 libgcc-3.4.3-22.1 2
2005 Nov 17
3
Custom kernel RPM/SRPM
Hi, I've built customs kernels from the SRPMs with the following: rpmbuild -bp --target=i686 /path/to/spec cd /usr/src ln -s /usr/src/redhat/BUILD/kernel-x.y.z/linux-x.y.z linux cd linux make oldconfig make menuconfig make all make modules make modules_install And it works just fine. The problem now is that I think installing that way isn't
2004 Dec 08
2
Center for Internet Security "scoring tool"
Hello, Has anyone tried out the security scoring tool at http://www.cisecurity.org/bench_freebsd.html? Any thoughts or opinions? Regards, stheg __________________________________ Do you Yahoo!? Yahoo! Mail - 250MB free storage. Do more. Manage less. http://info.mail.yahoo.com/mail_250
2011 Sep 26
1
Is gluster suitable and production ready for email/web servers?
I've been leaning towards actually deploying gluster in one of my projects for a while and finally a probable candidate project came up. However, researching into the specific use case, it seems that gluster isn't really suitable for load profiles that deal with lots of concurrent small files. e.g. http://www.techforce.com.br/news/linux_blog/glusterfs_tuning_small_files
2010 Jun 25
2
Virtualization as cheap redundancy option?
I'm wondering if virtualization could be used as a cheap redundancy solution for situations which can tolerate a certain amount of downtime. Current recommendations is to run some kind of replication server such as DRBD. The problem here is cost if there are more than one server (or servers running on different OS) to be backed up. I'd basically need to tell my client they need to buy say
2009 Oct 01
2
Reply to ICMP echo request (type 8) on different (ethernet) interface
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi list, I have a weird (?) problem here on a setup running CentOS 5.3 x86_64 (and OpenVZ, and some home-brew L2TP daemons, RIPd, BGPd, etc). There's a (VE in OpenVZ speak) virtual machine that has two ethernet interfaces, seen as eth0 and eth1, respectively. Those live in VLANs, but it's not important here. The thing is that on eth1 the