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May
6
revised Serial connections on network
added 4 characters in body
May
6
comment Serial connections on network
This is just false. Point-to-point links do not need their own IP address.
May
6
answered Serial connections on network
May
6
comment VERY peculiar permission masks, UIDs, GIDs and file names in Linux
This is why RAID is not backup.
May
6
comment Calculating the round trip time for ping packets
Calculate the time until the first bit reaches the next hop. Then calculate the time between when the first bit gets somewhere and when the last bit gets somewhere. Sum them, and you have the time it takes a packet to go one hop.
May
6
comment ksoftirqd process overloads CPU with high-bandwidth and multiple network connections
What are your current rx-usecs and InterruptThrottleRate settings? Perhaps you have things set to minimize latency rather than maximize throughput.
May
6
comment Troubles with memcache.so
Rebuild memcached with -fgnu89-inline in CFLAGS/CXXFLAGS. What happens is the inline keyword under new rules causes _mmc_queue_pop to inline in all instances, leaving nothing for memcache.so to dynamically link to.
May
5
comment Freshly formatted ext4 drive appears to have several gigabytes already used
If you're not going to use the drive to store predominantly large files, using -T largefile will make inode allocation much less efficient as the drive gets full. You're much better off reserving more and then letting the system release it if doesn't need it than reserving too little and forcing the system to scrounge for fragments when the drive is full.
May
5
comment Freshly formatted ext4 drive appears to have several gigabytes already used
It's just temporarily reserved for inodes. If you turn out not to need it, it will be reclaimed. It's inefficient to reserve space in small bits and pieces.
May
5
comment Redirect traffic between two ports with iptables
You don't need anything but the one-line rule you posted. TCP is connection-oriented. Packets going in one direction on the connection always have precisely the same source IP address and port as the destination IP address and port of packets going in the other direction. This is an absolute TCP requirement -- it is impossible to violate it.
May
5
comment Forward DHCP assignment to my ISP rather than have router's DHCP server assign IPs
If your ISP offers this service (multiple IP addresses for a single connection), then it should work. Turn off your router's DHCP server and set the router to bridging mode. If it's a pure Ethernet router, connect the modem to a LAN port rather than the WAN/Internet port. Note that most ISPs just don't do things this way.
May
4
comment Access ports versus trunk ports?
And therefore, trunks can be used to connect endpoints that support VLAN tagging. And access points can be used to connect a single VLAN to dumb switches that don't.
May
4
comment Regarding routing packets via one computer to another
And should Z see them coming from Y so replies go back to Y? Or should Z them coming from X and send replies to X?
May
4
comment Regarding routing packets via one computer to another
How will Y know which packets it should forward to Z? And what layer are you trying to do this at? Is this NAT? Or proxying? Or what? (We could probably give you a much better answer if we knew what problem you were trying to solve.)
May
4
comment Cluster fails because of network loop
What makes you think the iSCSI dropped out? It looks like the cluster nodes lost their ability to talk to each other over the LAN.
May
2
comment windows server 2003 socket connections limit
You can minimize your non-paged pool consumption. Use only one listening socket. Post the smallest IOCP buffers you can get away with. Defragment the IOCP buffers so they comprise as few pages as possible. (If you use 2KB IOCB buffers, you can pack them 4 to a page. Be careful as the OVERLAPPED structure counts!)
May
2
comment Why this recursion in tracert hops?
No, that is fundamentally not how the Internet works. Each network sets its own policy based on who it pays money to and packets leaving that network use that network's routing policy. Each network typically routes each packet based solely on its destination IP address and where it entered the network. The network does not learn from packets.
May
2
answered Why this recursion in tracert hops?
May
2
comment windows server 2003 socket connections limit
Triple-check your MaxUserPort registry entry. (Make sure it's spelled right. Make sure it's 65534 decimal. Make sure it's a DWORD.)
May
2
comment windows server 2003 socket connections limit
What goes wrong when you try to create 6,000 server sockets? What function fails (socket? bind? listen?) And what error do you get? Also, is there some specific reason you are using so many listening sockets?